The White House said Monday that US strategy would not change in Afghanistan despite the fallout from a US soldier's shooting rampage which killed 16 civilians in a new jolt to America's war policy.

"Our strategic objectives have not changed and they will not change," White House spokesman Jay Carney said, adding Washington remained committed to disrupting, disarming and defeating Al-Qaeda and training Afghans to ensure their own security.

President Barack Obama is committed to gradually withdrawing US forces from Afghanistan under an agreement with NATO partners which foresees a full drawdown by the end of 2014.

"This is a challenging time, no question," Carney said, but added that the administration would continue to work on what it sees as vital US national security interests in Afghanistan.

"I don't believe this incident will change the timetable of a strategy that was designed and implemented to allow for the withdrawal of US forces, to allow for the transfer of lead security over to the Afghans," he said.

Carney added that discussions about the pace of the drawdown have been ongoing with US allies "and will certainly be a subject of discussion among heads of state at the NATO meeting in Chicago in May."

Carney pledged that US military and political officials would continue to work with the Afghan government and military to "investigate this tragic incident and make sure there is accountablity."

The American soldier walked off his base in southern Kandahar province and broke into three village homes before dawn Sunday, killing 16 people including women and children -- an event described by Afghan President Hamid Karzai as "unforgivable."

(A villager points to a spot where a family was allegedly shot in their home by a rogue US soldier in Alkozai village of Kandahar province. An AFP reporter counted 16 bodies -- including women and children -- in three Afghan houses after the shooting rampage. AFP Photo/Mamoon Durrani)