WASHINGTON: Vice President Joe Biden on Monday insisted the US-led war effort in Afghanistan showed promise and that it was too soon to judge it a failure.

Biden, speaking to military veterans, also said a July 2011 deadline for the start of a troop withdrawal would not signal a US departure, but merely the beginning of a gradual handover to Afghan security forces.

The war in Afghanistan had been neglected in the past and Washington had only recently put in place a clear strategy and enough troops, Biden told the Veterans of Foreign Wars in Indianapolis, Indiana.

"So, folks, don`t buy into `we have failed in Afghanistan.` We now are only beginning with the right general and the right number of forces to seek our objectives," said Biden, referring to newly appointed commander General David Petraeus.

The US vice president struck an optimistic tone on Afghanistan and the scaled back US role in Iraq in his speech, despite declining public support for the Afghan war and mounting casualties.

Biden cited how President Barack Obama had more than tripled the American force in Afghanistan since coming into office in 2009, with 100,000 troops now on the ground.

With sufficient forces deployed, the United States is "making measurable progress" towards disrupting and defeating Al-Qaeda in Afghanistan, he said.

As for the July 2011 date for the start of a drawdown, Biden said setting the deadline was vital to convey to Afghan leaders the need to take responsibility for security.

"They must exercise sovereignty if they`re ever going to prevail, and also we state it as a goal that we should strive for," he said, saying similar deadlines had forced Iraqis to "step up."

"We cannot want peace and security in Afghanistan more than they want it," he added.

The Obama administration has struggled to explain the mid-2011 deadline at home and abroad, with officials offering differing interpretations and critics charging the target has created needless confusion.

Defense Secretary Robert Gates has said the July 2011 date is set in stone, while the US and NATO commander in Afghanistan, Petraeus, has said he might recommend against a withdrawal depending on conditions on the ground.

BDST: 03:30 HRS, August 24, 2010