WASHINGTON - President Barack Obama and South Korean President Lee Myung-bak are expected to show a united front against North Korea when they meet on Tuesday, but they may not make much progress on free trade pact that has been stalled for two years.

I don't think you'll see any daylight between President Lee and President Obama in terms of North Korea, said Victor Cha, who was a White House adviser on North Korean issues to former President George W. Bush.

The South Korean leader has followed a tough line on North Korea, even before Pyongyang raised tensions in recent weeks by test-firing missiles, restarting a plant to produce arms-grade plutonium and holding a May 25 nuclear test.

Lee's insistence that any new aid to Pyongyang depends on impoverished North Korea making progress in six-party nuclear disarmament talks shows how close Washington and Seoul are now aligned on that issue, Cha said.

But a free trade pact signed in June 2007 under Bush and late President Roh Moo-hyun and worth billions of dollars in new trade to each country could be the awkward elephant in the room when Obama and Lee meet, said Steven Schrage at the Center for Strategic and International Studies.

During last year's election campaign, Obama said the accord's auto and other manufacturing provisions favored South Korea too much and he urged Bush to renegotiate it.


Since taking office, Obama has directed U.S. trade officials to work with Seoul to resolve concerns over barriers to South Korea's market while also committing tens of billions of dollars in U.S. taxpayer money to prop up Chrysler and GM.

The U.S. International Trade Commission in 2007 estimated the pact would boost U.S. exports about $10 billion to $11 billion and have a negligible impact on the U.S. auto industry because increased imports from South Korea would mostly displace other suppliers.

Lee has enthusiastically embraced the deal and met with U.S. Trade Representative Ron Kirk on Monday to discuss it.

But Seoul has refused to renegotiate the auto provisions that many U.S. lawmakers find objectionable, saying it made significant concessions in the original deal.

Lee also faces problems at home winning approval for the pact. Opposition lawmakers are blocking parliament from meeting until Lee apologizes for a corruption probe that appears to have prompted Roh to commit suicide last month.

U.S. lawmakers have indicated that healthcare reform and energy legislation with take precedence this year over pending trade deals with South Korea, Colombia and Panama.

I wouldn't expect much more than a statement (from Obama and Lee) on the FTA's importance and the need to get it done in a reasonable time frame, said Troy Stangarone, congressional affairs director at the Korea Economic Institute.

The White House meeting follows North Korea's announcement on Saturday that it would start an uranium enrichment program and weaponize all its plutonium in response to fresh UN sanctions. Pyongyang also threatened military action if Washington and its allies tried to isolate it.

North Korea this month sentenced two U.S. journalists, Laura Ling and Euna Lee, to 12 years hard labor for grave crimes, saying they illegally entered the country.

(Additional reporting by Jon Herskovitz in Seoul; editing by Chris Wilson)