A senior U.S. congressional Democrat said he expected Congress to pass three trade agreements with South Korea, Colombia and Panama, despite his own strong concerns about the Colombia deal.

"I think they will most likely pass and I'm simply expressing my strong opinion of each of the three," Representative Sander Levin, the top Democrat on the House of Representatives Ways and Means Committee said.

President Barack Obama submitted the three trade deals to Congress on Monday, kicking what is expected to be a quick but potentially contentious drive to get them approved.

Opponents of the trade deals held a rally outside the Capitol Building on Tuesday to urge lawmakers not to vote for agreements, which will begin their journey through Congress on Wednesday with action in the House Ways and Means Committee. (Reuters)