Bush meets Obama ahead of presidents' lunch

WASHINGTON (Reuters) - President George W. Bush met successor Barack Obama for the second time at the White House on Wednesday ahead of a lunch with all living U.S. presidents some two weeks before Obama's inauguration.

Bush, a Republican, and Obama, a Democrat, were expected to discuss the crisis in the Middle East and U.S. economic challenges, White House spokeswoman Dana Perino said, in what was likely to be a 20 to 30 minute one-on-one visit.

Despite last year's heated political campaign when Obama attacked Bush regularly over foreign and domestic policy, the transition process between the November 4 election and Obama's January 20 inauguration has proceeded smoothly.

Their meeting took place ahead of a lunch with former Presidents Jimmy Carter and Bill Clinton, both Democrats, and Republican George H.W. Bush, the current president's father.

It will be the first such gathering of former U.S. heads of state at the White House in 27 years.

(Reporting by Jeff Mason; editing by David Wiessler)