The U.S. Congress’s efforts to ratify pending free trade agreements (FTA) with South Korea, Panama and Colombia are facing difficulties.

The U.S. Senate Committee on Finance’s plan to hold a "mock" markup on Thursday to discuss bills seeking the ratification of the three trade deals fell through due to opposition from Republicans.

Republican members of the committee boycotted Thursday’s meeting, stressing they would not take part in discussions centering around extending the Trade Adjustment Assistance (TAA) program as a way to support Americans affected by the trade pacts.

Senate Finance Committee Chairman Max Baucus denounced the Republicans for unilaterally refusing to take part in the discussions.

The mock markup would have been the last time for legislators to deliberate and amend proposed legislation on the FTAs before it is submitted for voting.

The Obama administration is pushing for the passage of the trade pacts before Congress goes into recess in August.