"We continue to work with the Russians, continue to negotiate and discuss with them the next steps," Agriculture Secretary Tom Vilsack told reporters earlier at a USDA event.

A USDA spokesman did not release the name of the facility that has yet to be approved, when that would occur or if the approval of this plant would mean the ban has been fully lifted.

Secretary Vilsack said last week Russia had "basically given us the sign-off" on about half of 26 poultry facilities for export, and the others should be approved "in the very near future."

Russia was the largest export market for US chicken before it put a ban in place in January. Russian officials were concerned about a chlorine rinse used in US processing plants to kill pathogens that can cause food poisoning.

Under the new requirements approved in July, US chicken companies can replace the chlorinated rinse with cetylpyridinium chloride, peroxyacetic acid or hydrogen peroxide.

"My understanding is poultry is on its way to Russia," Secretary Vilsack said.

US meat producers have ramped up shipments to Russia during the past monthreports Reuters.

Poultry producer Sanderson Farms Inc (SAFM.O) resumed exports to Russia in August, and Tyson Foods Inc (TSN.N) shipped its first load of poultry last week. Pilgrim's Pride Corp (PPC.N) planned to resume exporting chicken to Russia last Saturday.

The United States shipped 733,000 tonnes of poultry meat to Russia worth $752 million in 2009. The U.S. quota for 2010 was set at 600,000 tonnes, but Russia has allowed other suppliers to use a quarter of it.

Some analysts contend Russia enacted the ban to protect domestic production from competition.