The foreign and defense ministers plan to visit the National Assembly Friday to urge the swift ratification of a revised pact on sharing the cost of keeping U.S. troops here, officials said.

In January, the allies renewed their agreement on co-shouldering the financial burden of keeping 28,500 American forces here, but the agreement has been pending in the parliament due to the objections of the main opposition party. The previous five-year deal expired at the end of last year.

According to the officials, Foreign Minister Yun Byung-se and Defense Minister Kim Kwan-jin will meet with Ahn Hong-joon, the chairman of the foreign affairs committee, later Friday to call for the quick passage of the new pact.

The ministers are expected to call for Ahn's support for the deal's passage, they added.

The revised agreement will go into effect after the president signs it following parliamentary ratification.

It is feared a further delay in the pact's passage would result in South Korean workers employed by United State Forces Korea being put on unpaid leave due to a lack of funds.

Under the renewed five-year deal, the South agreed to pay 920 billion won ($852.6 million) this year for the upkeep of the U.S. troops, a 5.8 percent increase from a year earlier.

The Seoul-Washington defense treaty had initially put the burden of financing U.S. defense activities solely on the U.S. side. The allies signed their first defense cost-sharing deal in 1991, and the deal has since been renewed intermittently.

U.S. forces are stationed in South Korea mainly as a deterrent against North Korea, a legacy of the 1950-53 Korean War. (Yonhap)