UPDATE 2-USTR ready to discuss S. Korea deal with Congress

* USTR says ready for final talks on implementing bill

* Republicans push for action on Panama, Colombia deals (Adds Republican comment, more detail)

By Doug Palmer

WASHINGTON, March 7 (Reuters) - The Obama administration said on Monday it was ready to begin final talks with Congress on a bill to implement a free trade deal with South Korea, but it was silent on pacts with Colombia and Panama that top Republicans also want approved.

U.S. Trade Representative Ron Kirk, in a letter to key members of Congress, said his office hoped to "commence without delay" talks on legislation to implement the U.S.-South Korea free trade agreement, which was signed in June 2007.

The pact would be the largest U.S. free trade deal in more than 15 years and solidify ties with a longtime ally in the fast-growing Asia Pacific region, which already accounts for a huge share of world trade.

The U.S. auto industry fiercely opposed the agreement as originally negotiated, arguing it failed to tear down regulatory and other barriers that had long kept American cars out of the South Korean market.

For most of its first two years in office the Obama administration made little effort to resolve those concerns as it pursued other priorities, including a sweeping healthcare overhaul and changes to the financial regulatory system.

However, after Republicans won control of the U.S. House of Representatives late last year, the White House renegotiated the pact to win more favorable terms for U.S. automakers.

Since then both Ford Motor Co (F.N) and the United Auto Workers union have endorsed the agreement, although many labor groups remain opposed to it.

Labor groups also strongly oppose the Colombia agreement, saying that the Andean nation has not done enough to stop killings of union members and to prosecute those responsible.

The Panama pact is less controversial, but it has been held back partly because of the concerns over the Colombia pact.

House Ways and Means Committee Chairman Dave Camp, a Michigan Republican, repeated on Monday that he wanted Congress to consider all three trade agreements by July 1 and complained the administration had ignored bipartisan appeals to move forward on the Colombia and Panama pacts.

Senator Orrin Hatch, the top Republican on the Senate Finance Committee, said he would be press for "concrete answers" on how the administration plans to resolve remaining issues with Panama and Colombia when Kirk testified before the panel on Wednesday.

Both Camp and Hatch stopped short of saying Republicans would block action on the South Korea pact without progress on the other two trade deals. Together with Senate Finance Committee Chairman Max Baucus, a Montana Democrat, they said technical talks with the administration on the Korea legislation had already begun and would continue.

The U.S. International Trade Commission has estimated the pact, which cuts tariffs on agricultural and manufactured goods, would boost U.S. exports to South Korea by $10 billion to $11 billion annually and increase U.S. imports by $6.4 billion to $6.9 billion

The Obama administration plans to send Congress legislation to implement the deal using presidential "fast track" authority, which requires lawmakers to vote 'yes' or 'no' on the overall agreement without making any changes.

By tradition, the White House works closely with the House Ways and Means Committee and the Senate Finance Committee during the drafting of such bills to enable lawmakers to have an opportunity to address concerns.

(Reporting by Doug Palmer; Editing by Paul Simao)