The White House yesterday offered to negotiate with congressional Democrats over enforcing labour rights provisions in a trade agreement with Central America and the Dominican Republic, the latest sign that the administration fears the proposed deal is in jeopardy.

President George W. Bush met more than a dozen Democrats who had raised concerns that weak labour standards in the region could undercut US workers. It was his fourth meeting with members of Congress to try to build support for the Central American Free Trade Agreement (Cafta).