Washington, facing the closure of a key military air base in Kyrgyzstan, is looking for ways to diversify supply routes for US and NATO troops fighting in Afghanistan.

"Uzbekistan has given permission to allow the transit of non-military cargo to Afghanistan ...," Uzbek President Islam Karimov was quoted as saying by Interfax news agency.

Turkmen leader Gurbanguly Berdymukhamedov, in Uzbekistan on a visit, was quoted as saying his country had also agreed to allow supplies to pass through its territory.

"We have nothing against allowing humanitarian cargo to use our air space," he was quoted as saying by Interfax.

Both nations share borders with Afghanistan and have in the past indicated they sought to step up cooperation with NATO over Afghanistan. Russia has also previously agreed to allow NATO-led forces to send non-lethal cargo through its land.

Last week, Kyrgyzstan gave Washington six months to close its military air base on its territory, complicating US plans to boost the number of its troops fighting in Afghanistan .