WASHINGTON  -- Former Dallas mayor Ron Kirk, apparently on course to be the next U.S. trade representative, told senators Monday that his main objective as the nation's top trade official will be enforcing existing law and insisting that U.S. trade partners play by the rules.

Revelations that Kirk, like several other Obama administration nominees, had tax payment problems, were barely mentioned in the abbreviated confirmation hearing of the Senate Finance Committee.

Committee Chairman Max Baucus, D-Mont., noted that Kirk had made "regrettable but, I believe, honest mistakes," and added that the nominee had taken steps to remedy them. A confirmation hearing set for last week was postponed after the committee made it known that Kirk had underpaid the IRS by some $10,000 earlier in the decade.

"I believe that you are the best man for the job," Baucus said. Republicans on the committee did not raise the tax issue, and none voiced opposition to Kirk's nomination. The hearing was cut short as senators had to leave for a long series of votes on the Senate floor.

Kirk, generally supported by the business community as an advocate of expanded trade, made clear that trade policy under President Barack Obama would differ from that of the Bush administration, when the emphasis was on cementing new free trade agreements.

Kirk said he did not come to the job with "deal fever" and would make his top priority assuring that existing trade partners live up to the rules -- in such areas as labor rights and environmental protection -- that are already on the books.

He said that of the three pending bilateral free trade deals -- with Panama, Colombia and South Korea -- Panama was the closest to being sent to Congress. He said the agreement with South Korea offered "one of the biggest opportunities we have" to expand U.S. sales abroad, but that the current accord "just simply isn't fair. " He said that the administration "will step away from that if we don't get it right."

Baucus, a supporter of free trade, said that with the world economy in shambles and protectionist sentiments growing, Kirk will face pressure to oppose new trade deals. "Your job will be to fight a rearguard action to combat new barriers to trade," he said.

Last week 350 union, environmental, farm and faith groups sent a letter to Congress stressing that the recent election demonstrated "a relentless demand from the American public" for changes in trade policy. They said negotiations with China over a bilateral investment treaty should be halted and that not one of the three pending free trade agreements can pass a "do no further harm" test.

They said Panama's economy relies on banking secrecy and money laundering, Colombia has a history of violence against union and civil rights groups, and the deal with South Korea includes major financial service sector deregulation and doesn't correct the imbalance in automobile trade.
Kirk said all three agreements would undergo a comprehensive review before they are presented to Congress.

On the other side, the top Republican on the committee, Sen. Charles Grassley of Iowa, said Obama risked losing the support of Republicans if he tries to reopen a 2007 compromise between the Bush administration and congressional Democrats under which labor and environmental concerns were given greater weight in future trade agreements.

"I believe we've already addressed these issues in good faith, and it's time now to focus on implementing our pending trade agreements," Grassley said.

Grassley also questioned Kirk about Obama's "mixed signals" on the 1994 North American Free Trade Agreement with Mexico and Canada. During the campaign Obama called for renegotiating the pact, which is highly unpopular in states that have seen a decline in manufacturing jobs, but he since has tempered his remarks.

Kirk assured Grassley that any efforts to "strengthen" NAFTA would be collaborative and would not result in any of the participants raising tariffs, a concern to farmers in Grassley's home state.

Kirk also told Baucus that the stress on enforcement would apply to two issues of importance to the Montana senator, an ongoing dispute with Canada over softwood lumber trade and the European Union's barriers to the importing of U.S. beef.