WASHINGTON - President Barack Obama plans to send the U.S.-South Korea free trade agreement to Congress in the next few weeks, but "serious issues" are holding up deals with Colombia and Panama, his top trade official said Wednesday.

U.S. Trade Representative Ron Kirk told the House Ways and Means Committee that Obama hopes Congress will approve the South Korean pact this spring. The administration says that accord could mean billions of dollars in increased U.S. exports and create tens of thousands of jobs.

Kirk failed to satisfy majority Republicans about progress in finalizing the Latin American agreements. He said Obama had directed him to intensify talks with Colombia and Panama, but "there remain serious issues" including labor rights issues, to be resolved before the administration submits the deals to Congress.

Under President George W. Bush, the U.S. signed free trade deals with the three countries in 2007. But the agreements don't go into effect until Congress approves them, and the Democrats who have controlled Congress have not made trade a priority.

The Republican takeover of the House in November has moved trade into the spotlight, and the U.S.-South Korea deal took a big step forward in December when the two countries agreed on steps to open up Seoul's previously closed auto market.

The House committee chairman, Rep. Dave Camp (R-Mich.), applauded progress with South Korea but pushed the administration to wrap up the other two trade pacts. "Where is the path forward for those agreements?" he asked.

He said that the three agreements could translate into more than $10 billion in increased exports and could create up to 250,000 American jobs. Camp said the failure to act is ceding markets to other competitors, including the European Union and Canada.

"Time is up for Panama and Colombia," said the chairman of the trade subcommittee, Rep. Kevin Brady (R-Texas). Colombia and Panama "have not only done everything we asked but have gone far beyond."

The United States has pressed Panama to change laws that have made it a tax haven and to improve its labor rights record. The main issue in Colombia has been labor rights, including violence against labor leaders.

Kirk said the administration is encouraged by commitments by the new government in Colombia to improve that situation. He said he planned to send a team to Colombia in the next few weeks for further discussions.

While citing progress in both countries, he told Republicans pressing for a timetable for action that "we will not sign agreements just for agreements' sake."

The top Democrat on the committee, Rep. Sander Levin of Michigan, echoed that sentiment and said that Democrats had improved past free trade agreements by holding out for tougher provisions on worker and environmental protection.

He said union worker violence in Colombia remains unacceptably high and the burden is on the Colombians to address the issue.

Colombia's ambassador to the United States said in a statement that he welcomed Kirk's efforts to move the trade agreement forward this year, but he took issue with criticisms of his country's human rights record. "To suggest that for years Colombia has stood idly by and not taken aggressive steps to protect human and labor rights, and enhance union rights and the rule of law, are claims not based on current facts," said Gabriel Silva.

Levin and other Democrats also expressed concern that GOP leaders have shelved legislation that would extend a program that helps workers who lose their jobs because of imports. The program expires next week. Some Republicans either don't like it or want to use it as leverage to get the administration to act on the free trade deals. Levin said tens of thousands of affected workers are at risk if the program expires.

Camp said the lack of commitment on Panama and Colombia "is hindering the rest of our trade agenda."