GUADALAJARA, Mexico -- U.S. President Obama backed off campaign pledges to "amend" NAFTA and promised he would do what he could to re-launch the Mexican cross-border truck project.

The statements were made over the weekend at a NAFTA summit in Mexico with Canadian Prime Minister Stephen Harper and Mexican President Felipe Calderon.

The U.S. President reaffirmed "the need to reject protectionism."

Later, an Obama administration official told Reuters, "I think there's been a clear understanding that [the cross border trucking issue] was one that is a priority issue and one that everyone would like to see resolved as quickly as possible."

Immediately after Congress passed a bill canceling the Bush administration's Mexican truck demonstration project, Mexico slapped $2.4 billion in retaliatory tariffs on about 90 U.S. goods.

There were reports last month that a new trucking proposal has gone through the interagency channels and will be passed along to Capitol Hill for a vote.

Meanwhile, Obama seemed was less enthusiastic about quelling Canadian anxiety over U.S. protectionist policies.

Obama downplayed the impact of Buy American -- a rule that shuts out foreign companies from bidding on or supplying projects funded by the President's multi-billion-dollar stimulus package. 

He said it's an isolated issue that does not affect the majority of trade between Canada and the U.S.

While it's far from the most important NAFTA issue for Obama, the president at least acknowledged it's top of mind for Canadians, noting that Prime Minister Stephen Harper raises the issue "every time (he) see(s) him."