Washington confirmed Monday that it wants to withdraw 12,500 troops from South Korea as part of a global review of its military posture designed to produce a more agile fighting force for the 21st century.

South Korea is still technically at war with North Korea and the announcement triggered alarm in a country gripped by uncertainty for the past 20 months over the Stalinist state's nuclear weapons drive.

South Korean officials said the troop withdrawal announcement was formulated as a proposal, rather than a final decision, and Seoul was busily preparing its own counter-proposal.

Washington, facing immediate pressure for fresh troops for duty in Iraq, said the pullout would take place within 18 months. Seoul wants the deadline pushed back.

The troop withdrawal proposal was announced on the sidelines of talks on realigning US forces from positions close to the border with North Korea to bases south of Seoul and includes a previously announced redeployment of 3,600 troops from South Korea to Iraq.

The number and type of troops implicated in the proposed withdrawal was still up for discussion, National Security Adviser Kwon Chin-Ho was quoted as saying in a pool report.

"The timetable is nothing but a suggestion from the United States and we need to examine and negotiate it," Kwon said before attending a cabinet meeting presided over by President Roh Moo-Hyun.

"In the reviewing process, we also need to closely consult on which US troops in Korea should be moved."

Defense Minister Cho Young-Kil, in the same pool report, referred to the troop withdrawal announcement as a "suggestion" that was subject to modification.

South Korean security-related ministries were discussing the proposal and would soon present Washington with recommendations, he said.

Media reports said South Korea wanted a delay of several years in the plan for the biggest troop withdrawal from South Korea since the Vietnam War and its first troop pullout from the country in over a decade.

The timeframe should be pushed back to between 2007 and 2113 to allow South Korea to complete a 10-year plan to upgrade its own military forces, according to some reports.

North Korea, which has campaigned strenuously for a pullout of all 37,000 US troops from South Korea, was expected to view the planned troop withdrawal with suspicion.

The Stalinist state earlier condemned US plans to realign its forces in South Korea away from the heavily-fortified border with North Korea as a sinister plot to prepare a pre-meditated strike and trigger the second Korean War.

Talks were in their second day here Tuesday between top US and South Korean officials on the realignment plan that includes the removal of the Yongsan garrison, headquarters of US forces in South Korea, from the capital to a location further south.

North Korea on Monday reiterated its call for a complete US troop pullout on an Internet website operated by Pyongyang, Yonhap news agency said.

It referred to the plan to redeploy 3,600 troops stationed here to Iraq as a "cunning trick" aimed at calming anti-US sentiment building in South Korea as a result of oppositon to Iraq and the hardline US stance on the North Korean nuclear standoff.

In South Korea, conservatives condemned the announcement and blamed President Roh and his left-leaning administration which rose to power on a wave of anti-Americanism and has advocated a more independent stand from the United States.

Legislative elections on April 15 tipped the balance further to the left as reformers loyal to Roh took control of the National Assembly.

The conservative opposition Grand National Party described the plan as "shocking and surprising" and its senior lawmaker Park Jin said it would undermine South Korean security.

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