The United States would be willing to send troops to Pakistan to help fight Islamist militants, US Defence Secretary Robert Gates said last night.
"We remain ready, willing and able to assist the Pakistanis and to partner with them, to provide additional training, to conduct joint operations, should they desire to do so," Mr Gates said.
He added Pakistan had not requested such a move and Washington had not presented proposals to Pakistan's leaders.
The United States, waging wars in Iraq and Afghanistan that have strained its military, is increasingly concerned about the rise of insurgents in Pakistan's tribal areas bordering Afghanistan.
Those areas have become safe havens for Taliban and al-Qaeda militants, according to US officials.
Washington has given nuclear-armed Pakistan about $10 billion in aid since 2001, when Islamabad dropped support for the Taliban movement in Afghanistan and joined the US-led campaign against terrorism after the September 11 attacks.
The United States already helps train Pakistani forces.