There is a new crisis on the agenda for President Barack Obama.

While trying to revitalize a nosediving economy, rebuild the collapsing auto industry, rein in North Korea’s unpredictable Kim Jong-il and overhaul the costly healthcare system, Obama now can ponder his response to an Iran reeling from a disputed election and the biggest street protests since the 1979 Islamic revolution.

Several leading Republicans have hammered Obama for what they say is a too cautious approach to the disputed vote that gave hardliner President Mahmoud Ahmadinejad a big win over former Prime Minister Mirhossein Mousavi. Obama said on Monday he was “deeply troubled” by the post-election violence but it was up to the Iranians to work out who their leaders will be.

Republicans say that is not good enough.

“He should speak out that this is a corrupt, fraud, sham of an election.  The Iranian people have been deprived of their rights,” Senator John McCain said on NBC’s “Today” show on Tuesday.

While Obama considers his next move on Iran, however, he will also grapple with North Korea during a White House meeting on Tuesday with South Korean President Lee Myung-bak. The South Korean leader has taken a tough line on North Korea even before Pyongyong ratched up tension in recent weeks by test-firing missiles, restarting a plant to produce weapons-grade plutonium and holding a May 25 nuclear test.