LAGOS (Reuters) – Nigerian Vice President Goodluck Jonathan’s takeover as acting head of state eases immediate concerns over who is in charge but political uncertainty will persist until the next presidential elections are held. Jonathan moved quickly to stamp his authority after assuming presidential powers, with a wide-ranging broadcast to the nation in which he pledged to prioritize peace in the oil-producing Niger Delta, punish those behind religious unrest and work toward credible national elections next year.

“It is now time for us to move on in a more determined manner to tackle the various challenges which we face as a nation,” he said in the address late on Tuesday.

But his route to assuming power as acting head of state has no precedent in Nigeria and is not explicitly backed by the constitution, leaving him open to legal challenges from opponents and potentially weakening his ability to lead.

Political power brokers will likely exploit the uncertainty as they battle over who the ruling People’s Democratic Party nominee should be in presidential elections due in April 2011.

LAGOS, Jan 30 (Reuters) – Nigeria’s main militant group called off a three-month old ceasefire in the oil-producing Niger Delta on Saturday and threatened to unleash an "all-out onslaught" on Africa’s biggest oil and gas industry. The announcement by the Movement for the Emancipation of the Niger Delta (MEND) could not come at a worse time for Nigeria, with President Umaru Yar’Adua in hospital in Saudi Arabia and uncertainty over who is in charge of the country. For a full story, click on [ID:nLDE60T004] PRESSURE ON THE PRESIDENCY MEND’s announcement piles further pressure on Nigeria’s leaders to resolve the impasse over who is in charge. Yar’Adua has been in Saudi Arabia for more than two months receiving treatment for a heart condition but has failed to formally transfer powers to Vice President Goodluck Jonathan, bringing the country to the brink of constitutional crisis. A federal high court has said Jonathan can perform presidential duties but not be acting president, a ruling which leaves unclear his authority to act as commander-in-chief of the armed forces should an additional military deployment in the Niger Delta be required. The Senate, former heads of state and ex-ministers, the Nigerian Bar Association and the opposition have all called on Yar’Adua to formally notify parliament of his absence and allow Jonathan to take over until his health is restored. But the ruling party has said Yar’Adua remains fit enough to govern and the cabinet has twice passed resolutions saying there is no need for him to hand over power. Yar’Adua was the driving force behind an amnesty programme last year which saw thousands of gunmen including key MEND field commanders hand over weapons in return for clemency and the promise of stipends, re-training and investment in the region. But community leaders had said Yar’Adua’s prolonged absence was stalling the amnesty programme and forcing former rebels to re-think their participation. There have been frequent protests over the non-payment of stipends. [ID:nLDE60A0WU] MEND accused the government of acting "like a victor over a conquered people" after the amnesty, and although Jonathan is from the Niger Delta region he is unlikely to be able to quickly win back the trust of disillusioned former rebels. OIL INDUSTRY IMPACT MEND was significantly weakened by last year’s amnesty programme, with several of its top field commanders handing over their weapons in return for clemency. It is unclear who is in charge and what operational capacity the group has left. But oil infrastructure in the delta, a network of thousands of shallow creeks opening into the Gulf of Guinea, is extremely exposed with thousands of kilometres (miles) of pipeline passing through remote and thickly-forested terrain. "To damage a pipeline just takes one youth who is able to swim and carry a beer bottle that is filled with sand and petrol," Emmanuel Uduaghan, governor of Delta state, one of the three main states in the region, said last month. Unrest in the region in the three years from early 2006 prevented the OPEC member from pumping much above two-thirds of its 3 million barrels per day installed capacity and the insecurity has been a major deterrent to new investment. Nigeria’s light crude is popular with U.S. and European refiners as it is easily processed into fuel products. Attacks on the country’s energy infrastructure helped lift global oil prices to record highs near $150 a barrel in 2008. Nigeria also holds the world’s seventh-largest proven gas reserves and supplies 10 percent of global liquefied natural gas. Leading U.S. oil companies ExxonMobil <XOM.N> and Chevron <CVX.N>, Royal Dutch Shell <RDSa.L>, Italy’s Agip <ENI.MI> and France’s Total <TOTF.PA> have all seen their operations affected by unrest in the past. MEND said on Saturday it would also start targeting oil services companies, which it said had seen a boom in business as they repaired pipelines damaged in its previous campaigns. ECONOMIC IMPACT The violence in the Niger Delta, which has included kidnappings, pipeline bombings and oilfield raids, had been costing sub-Saharan Africa’s second-biggest economy $1 billion a month in lost oil revenues, according to the central bank. Central Bank Governor Lamido Sanusi said last year that growth in Nigeria hinged largely on a solution being found to the unrest in the region. [ID:nL5273925] The insecurity has been a major deterrent to new investment. Hundreds of foreign workers have been kidnapped in the region. Most are quickly released after payment of a ransom, but companies in sectors ranging from energy to telecommunications and construction have withdrawn non-essential staff. POLITICAL IMPLICATIONS The amnesty programme and resulting lull in violence of several months had been seen as one of relatively few significant achievements of Yar’Adua’s nearly three-year-old administration. His absence from the political scene will make it difficult for the government to get the amnesty programme back on track should MEND carry out its threat to resume attacks. Of greater concern is the prospect of instability in the heartland of Nigeria’s mainstay industry at a time when the country is approaching national elections in 2011 without clarity over who is leading the country. Some of the factions which came together to form MEND originally enjoyed strong backing from politicians who used them to help rig elections. The campaign period for next year’s elections are expected to begin around June and analysts fear local political rivals could again exploit unrest in the Niger Delta to their own ends. (For more Reuters Africa coverage and to have your say on the top issues, visit: af.reuters.com/ ) (Writing by Nick Tattersall)

A man and his daughter outside a burned house in Jos,20 Jan 2010/Akintunde Akinleye

Four days of clashes this week between Christian and Muslim mobs armed with guns, knives and machetes killed hundreds of people in Jos and surrounding communities before the military was deployed to contain the violence. At least 460 people have been reported killed

The unrest around the capital of Plateau state, which lies at the crossroads of Nigeria’s Muslim north and predominantly Christian south, underscores the fragility of Africa’s most populous nation as it approaches the campaign period for 2011 elections with uncertainty over who is in charge.  President Umaru Yar’Adua has been receiving medical treatment in Saudi Arabia for two months.

Following is a timeline of religious and ethnic violence in Nigeria:

LAGOS (Reuters) – A Nigerian man charged with trying to blow up a U.S. passenger jet on Christmas Day began his journey in Ghana and spent less than 30 minutes in Nigeria’s Lagos airport, the Nigerian government said on Thursday.

Umar Farouk Abdulmutallab has been charged with trying to blow up Northwest Airlines flight 253 as it approached Detroit from Amsterdam on December 25 with almost 300 people on board.

“Further investigations by the Nigerian government have revealed that Abdulmutallab spent less than 30 minutes in the Nigerian airport before boarding the flight to Amsterdam,” Information Minister Dora Akunyili said in a statement.

“He arrived in Nigeria on 24 December from Ghana via Virgin Nigeria. His passport was scanned on entry into Nigeria at 20:08 and was scanned in at check-in for departure to Amsterdam at 20:35,” she said.

LAGOS, Dec 31 (Reuters) – A Nigerian man charged with trying to blow up a U.S. passenger jet on Christmas Day began his journey in Ghana and spent less than 30 minutes in Nigeria’s Lagos airport, the Nigerian government said on Thursday.

Umar Farouk Abdulmutallab has been charged with trying to blow up Northwest Airlines flight 253 as it approached Detroit from Amsterdam on Dec. 25 with almost 300 people on board.

“Further investigations by the Nigerian government have revealed that Abdulmutallab spent less than 30 minutes in the Nigerian airport before boarding the flight to Amsterdam,” Information Minister Dora Akunyili said in a statement.

“He arrived in Nigeria on 24 December from Ghana via Virgin Nigeria. His passport was scanned on entry into Nigeria at 20:08 and was scanned in at check-in for departure to Amsterdam at 20:35,” she said.

LAGOS, Dec 31 (Reuters) – Nigeria is on the brink of constitutional crisis with its ailing president not transferring powers to his deputy and political king makers feuding over his succession, a senior lawyer and a former U.S. envoy have warned.

President Umaru Yar’Adua has been absent from Africa’s most populous nation for more than a month receiving treatment for a heart condition in Saudi Arabia, but there have been no official updates on his health for weeks.

Vice President Goodluck Jonathan has been presiding over cabinet meetings but executive powers have not officially been transferred to him, leading to questions over the legality of decisions made by the government in Yar’Adua’s absence.

The Nigerian Bar Association (NBA), the umbrella body of all lawyers in the country, has launched legal action against the Attorney-General, asking a top court to declare that Yar’Adua has violated the constitution by omitting to transfer powers.

LAGOS (Reuters) – Nigeria will equip its international airports with full-body scanners next year after a 23-year-old Nigerian man tried to blow up a U.S. passenger plane on Christmas Day, an aviation official said on Wednesday.

Nigerian Civil Aviation Authority chief Harold Demuren said Nigeria had started the process of acquiring the machines, which use radio waves to generate a picture of the body that can see through clothing and spot hidden weapons or packages.

“These are new machines. Not many airports in the world are operating them right now, but Nigeria is determined because of the new face of the threat we are seeing, to acquire them,” Demuren told reporters in Lagos.

“This will be taking place in the New Year. We plan to acquire them at all our international airports,” he said.

LAGOS, Dec 30 (Reuters) – Nigeria will equip its international airports with full-body scanners next year after a 23-year-old Nigerian man tried to blow up a U.S. passenger plane on Christmas Day, an aviation official said on Wednesday.

Nigerian Civil Aviation Authority chief Harold Demuren said Nigeria had started the process of acquiring the machines, which use radio waves to generate a picture of the body that can see through clothing and spot hidden weapons or packages.

“These are new machines. Not many airports in the world are operating them right now, but Nigeria is determined because of the new face of the threat we are seeing, to acquire them,” Demuren told reporters in Lagos.

“This will be taking place in the New Year. We plan to acquire them at all our international airports,” he said.

The foiled Christmas Day bomb attack on a U.S. airliner has put further pressure on ailing Nigerian President Umaru Yar’Adua to either confirm he is fit to govern or hand over to his deputy.

Yar’Adua has been in Saudi Arabia for more than a month being treated for a heart condition and uncertainty over how a succession would be handled if his health worsens risks plunging Africa’s most populous nation into political crisis.

Vice President Goodluck Jonathan has been presiding over cabinet meetings but executive powers have not officially been transferred, leading a top lawyer to challenge the legality of decisions made in Yar’Adua’s absence.

Presidency officials have said Yar’Adua is responding to treatment and the government says state business is going on as normal.

LAGOS (Reuters) – The foiled Christmas Day bomb attack on a U.S. airliner has put further pressure on ailing Nigerian President Umaru Yar’Adua to either confirm he is fit to govern or hand over to his deputy.

Yar’Adua has been in Saudi Arabia for more than a month being treated for a heart condition and uncertainty over how a succession would be handled if his health worsens risks plunging Africa’s most populous nation into political crisis.

Vice President Goodluck Jonathan has been presiding over cabinet meetings but executive powers have not officially been transferred, leading a top lawyer to challenge the legality of decisions made in Yar’Adua’s absence.

Jonathan ordered Nigeria’s security agencies to work with the U.S. authorities to investigate the foiled December 25 attack, in which 23-year-old Nigerian Umar Farouk Abdulmutallab tried to detonate explosives on a passenger plane approaching Detroit, and the government has promised regular updates.