WASHINGTON — The White House Wednesday promptly rejected a call by three top senators for a halt to the withdrawal of US troops from Afghanistan following a spate of insider attacks on NATO forces.

Republicans John McCain and Lindsey Graham, and independent senator Joe Lieberman, called for a "strategic pause" to assess the damage of attacks by renegade Afghans, warning "we cannot afford to rush to failure in Afghanistan."

"Over the past three years, the Administration has repeatedly deployed fewer forces than our commanders recommended, and is now drawing down those forces in larger numbers and at a faster pace than our commanders advised," the senators said in a statement.

President Barack Obama "has said that the drawdown of US forces from Afghanistan would be responsive to conditions on the ground.

"We believe those conditions are now worrisome enough to justify an immediate suspension of further US troop withdrawals at this time," the senators said.

White House spokesman Jay Carney however said the Obama administration disagreed.

"The president believes that it is absolutely essential to continue with the transition to Afghan security lead, that after a decade of war -- more, in Afghanistan, it is time to wind down that war and to gradually transfer security responsibility to the Afghans," he said.

The US-led strategy for containing the Taliban insurgency involves a phased withdrawal of Western troops, and training Afghan forces that will take their place. The plan is for Afghans to be in charge of their own security by the end of 2014.

Carney said that the attacks on NATO troops by Afghan soldiers were "a very concerning problem."

"Action is being taken to protect against those kinds of attacks, but it does not change the mission," he said.

NATO said Tuesday it was scaling back joint operations with Afghan forces after an unprecedented number of Western soldiers were shot dead by their local colleagues.

All 33,000 extra troops sent to Afghanistan as part of the president's surge strategy announced in December 2009, are due to be home by the end of this month.

Decisions on the pace of future withdrawals in line with the 2014 deadline to hand over control of all of the country to Afghan forces are pending.