Admiral Mike Mullen, chairman of the US military’s Joint Chiefs of Staff, acknowledged that Obama’s plans to withdraw nearly a third of the some 99,000 US troops in Afghanistan by the end of next summer was a riskier plan than he had initially wanted. Obama announced the withdrawal timetable on Wednesday.

“The president’s decisions are more aggressive and incur more risk than I was originally prepared to accept,” Mullen told a House of Representatives committee hearing in his first comments on Obama’s plan.

Pressed by lawmakers, Mullen assured them the risks, although increased, were still manageable and would not jeopardize the military’s counter-insurgency mission.

His comments, while carefully phrased, were an unusually public expression of the Pentagon’s initial unease with Obama’s aggressive Afghan drawdown. In the run-up to Obama’s decision, military leaders lobbied privately for more time, and outgoing Defense Secretary Robert Gates publicly said any troop withdrawal should be modest.

US Secretary of State Hillary Clinton acknowledged “lots of competing opinions coming at (Obama) from all sides.” She, too, said she supported his decision.

In Kabul, Afghan President Hamid Karzai, Washington’s ally in a relationship made tense by allegations of incompetence and corruption, welcomed the plan for a gradual pullout and said Afghans increasingly trusted their security forces.

European nations that have contributed troops to the military effort against the Afghan Taleban insurgency said they would also proceed with already planned phased reductions.

But the Taleban, resurgent a decade after being toppled from power by US-led forces following the Sept. 11 attacks, dismissed the announcement and said only a full, immediate withdrawal of foreign forces could stop “pointless bloodshed.”

They rejected any suggestion of US military gains.

NO ‘RUSH TO THE EXITS’

In a prime-time televised appearance on Wednesday, Obama said he would withdraw 10,000 troops from Afghanistan by the end of 2011, and a further 23,000 by the end of next summer. Remaining troops would be steadily withdrawn after that.

Nearly 70,000 US soldiers will, however, remain in Afghanistan even after the cuts announced by Obama, about twice the number when he took office in January 2009.

Many lawmakers on Thursday criticized Obama’s decision, saying his aggressive timetable risked undermining the mission and could put US troops at greater risk.

“I think that’s a very dangerous thing to do,” Republican Senator Charles Grassley said, adding that he understood that General David Petraeus, the overall commander in Afghanistan, had recommended a slower withdrawal than the one Obama announced.

“The president’s only consideration in all of this should be what is best for our national security, not finding some halfway point” with war critics, Grassley told Reuters.

But Undersecretary of Defense Michele Flournoy, appearing at the committee hearing alongside Mullen, said, “Clearly, this is not a ‘rush to the exits’ that will jeopardize our security gains.”

Mullen played down the possibility that security gains could be easily reversed. Bringing home troops offered some benefits, including reinforcing the goal of putting Afghans in control of their security by the end of 2014.

“The truth is, we would have run other kinds of risks by keeping more forces in Afghanistan longer. We would have made it easier for the Karzai administration to increase their dependency on us,” Mullen said.

The Taleban has been pushed out of some areas of their southern heartland, but the insurgency has intensified along Afghanistan’s eastern border with Pakistan and US commanders have wanted to shift their focus to that area.

US officials are increasingly looking to a potential political solution, eventually bringing Taleban to the negotiating table. Clinton acknowledged preliminary outreach.

“We believe that a political solution ... is possible. The United States has a broad range of contacts at many levels across Afghanistan and the region ... including very preliminary outreach to members of the Taleban,” Clinton told a Senate hearing on Thursday.

She added that “this is not a pleasant business,” but part of efforts to end the insurgency.

In another sign of the challenges ahead in transferring control to Afghan authorities, an Afghan court on Thursday overturned a quarter of the results from last year’s fraud-tainted parliamentary election — potentially plunging the country into a new political crisis.

Afghanistan has been in a state of political paralysis since the Sept. 18 election, with a full cabinet still not in place after weeks of squabbling.

EUROPE CALLS FOR GRADUAL PULLOUT

As the US withdraws, so will its allies. France, Germany, Poland and Spain said they would proceed with a gradual drawdown.

French President Nicolas Sarkozy, like Obama seeking re-election next year, said in a statement that he would oversee a pullout “in a proportional manner and in a calendar comparable to the withdrawal of American reinforcements.” France’s 4,000-strong contingent is the fourth largest in Afghanistan.

German Defense Minister Guido Westerwelle said his country, with 4,800 troops in the increasingly violent north, hoped “to be able to reduce our own troop contingent for the first time” by the end of the year.