Top US commander Gen. David McKiernan says the mission in Afghanistan is likely to fail if militants continue to gain power in Pakistan.

During his 40-minute briefing, the commander of the US forces in Afghanistan said, "Can you get to the right end-state in Afghanistan if you have a deteriorating or failed state in Pakistan? The answer is probably no."

The remarks came as US Defense Secretary, Robert Gates, visited troops in Kabul to see "what they need to prevent militants from crossing into Afghanistan from Pakistan."

McKiernan predicted that the US would need at least 2 to 3 more years to finish its mission in Afghanistan, adding that it is the length of time that Kabul would need to train nearly 134,000 forces to ensure the country's security.

More than 60,000 US troops will be stationed in Afghanistan by the fall, when the nation is to hold elections.

Meanwhile, US President, Barack Obama, met with Afghan and Pakistani leaders in Washington to discuss security plans for both nations.

The meeting was however marred by reports of fresh US air strikes in the Afghan province of Farah that killed at least 150 civilians.

RZS/SME/RE