The United States has reportedly rejected Seoul's proposal to link Washington's plan to reduce its troops in South Korea with the relocation of the Yongsan Garrison.

Seoul wants to reduce the size of the site set for the new U.S. military headquarters in Pyeongtaek and Osan in proportion to the size of reduction of U.S. troops stationed on the Korean Peninsula.

A top government official said Thursday that the United States turned down the South Korean proposal at a recent bilateral working-level military meeting held in Washington.

According to recent reports, Washington plans to cut the U.S. military presence in South Korea by 12,000 troops - nearly one third of its 37,000 troops currently stationed in South Korea.

The latest development is casting a dark cloud over prospects for the 9th round of the Future of the Alliance Policy Initiative talks slated to open in Seoul next week.