Uribe’s invitation came after the Democratic-led House of Representatives delayed a vote on the free trade agreement, resisting pressure from US President George W. Bush to get the pact approved this year.”We want Ms. Nancy Pelosi, speaker of the House of Representatives of the United States, to visit Colombia,” Uribe said during an event in the Caribbean coastal city of Cartagena.US unions have strongly opposed the trade pact over concerns about violence against union activists in Colombia.The proposed trade deal has also made headlines in the US presidential election with Democratic candidates Barack Obama and Hillary Clinton voicing opposition to the pact.Bush used a presidential move on April 7 to give Congress a 90-day deadline to approve the FTA, but the House voted to change rules last week to delay a vote on the pact.The US president has warned that the FTA was crucial to US national security interests in the region, noting that Bogota has been the staunchest ally of the United States in Latin America.