Japan and the United States gave up on plans Tuesday to finalize an agreement by Friday on the realignment of U.S. forces in Japan, further prolonging negotiations that are testing the strength of the bilateral security alliance.

The U.S. has asked to postpone a meeting of senior defense officials scheduled for Thursday and Friday in Washington, citing the tight schedules of U.S. officials, said Defense Agency chief Fukushiro Nukaga.

The request sparked speculation that Washington canceled the meeting because talks had stalled between Tokyo and the northern Okinawa city of Nago, which has been asked to host a facility to replace the U.S. Marine Corps Futenma Air Station in Ginowan, central Okinawa.

Tokyo and Washington also remain at odds over cost-sharing for the transfer of some 8,000 U.S. Marines and their dependents to Guam from Okinawa.

Nago officials reportedly said Tuesday they cannot resume talks with the central government due to the sudden death of former Mayor Tateo Kishimoto, at least until after Kishimoto's funeral Sunday. Kishimoto was the mayor who agreed in 1999 to an earlier government plan to build an offshore civilian-military airport off Nago's Cape Henoko to replace Futenma.

The former mayor opposed the current proposal to build the replacement military-only airstrip along the Henoko coast and adjacent waters.

"(The talks' suspension) is unavoidable," Nukaga told reporters at a Tokyo hotel Tuesday night. "But if (the city) won't squarely sit at the table, we will have no choice but to proceed with the (original) government policy."

Nukaga, who met Prime Minister Junichiro Koizumi over dinner, quoted the prime minister as saying the government should stick to the basic Futenma relocation plan.