WASHINGTON — President Bush delivered an impassioned appeal yesterday for congressional approval of a free-trade agreement with Colombia, linking it to economic progress for the South American nation and to American security from terrorism.

Clearly directing his remarks at President Chavez, with whom the Bush administration has tangled repeatedly, the president said failure to enact the trade agreement would play into the hands of “antagonists in Latin America, who would say that … America cannot be trusted to stand by its friends.”

Mr. Bush also used his speech to the U.S. Hispanic Chamber of Commerce to deliver a forceful defense of the North American Free Trade Agreement, which Senators Clinton and Obama say has cost some Americans their jobs.

Mr. Bush has placed increasing emphasis on the Colombia pact in recent weeks, speaking about it with urgency and sending key members of his administration to meet with Democratic congressional leaders.

House Speaker Pelosi, a Democrat from California, opposes the agreement, arguing that the Colombian government has not done enough to curb violence against labor organizers. In a written statement yesterday, she cautioned the president against sending the pact to Congress without working out Democrats’ objections.

Many Colombian products already enter American duty-free under the 16-year-old Andean Trade Preferences Act, and the new pact would cement that arrangement. Administration officials argue that the new agreement would help level the playing field for American companies, eliminating Colombian tariffs as high as 35% on their products.

Yesterday, Mr. Bush indicated that he would send the measure to the Capitol soon after the Easter recess, which under the “fast-track” trade authority in effect when the agreement was signed would set a 90-day deadline for a vote, with no amendments or filibusters allowed.