WASHINGTON: The United States welcomed President Hamid Karzai's call for "dialogue and calm" Saturday as Obama backed moves from US Forces Commander John Allen in Afghanistan to protect NATO staff after the shooting of two US servicemembers.

Obama thanked Allen, commander of the NATO International Security Assistance Force, for "all of the measures he is taking to protect our servicemembers and civilians in Afghanistan and to encourage calm," the White House said in a statement.

The United States remains "committed to a partnership with the government and people of Afghanistan," after days anti-US protests sparked by the burning of Korans at a US-run military base.

"We welcome President Karzai's statement this morning encouraging peaceful expressions, and his call for dialogue and calm," the White House said.

The Pentagon earlier Saturday decried as "unacceptable" the killing of two US military advisers in Kabul as it called on Afghan authorities to better protect coalition forces and curtail raging violence.

NATO on Saturday pulled all its staff out of Afghan government ministries as anti-US protests raged for a fifth day.

The two Americans, working as International Security Assistance Force officers in the NATO coalition, were in the interior ministry when "an individual" turned his weapon against the pair, NATO said.

In the call Saturday Obama also expressed condolences to General Allen and to the victims' families after the shooting.

Taliban insurgents claimed responsibility for the shooting, saying it was in revenge for the burning of Korans at a US-run military base -- an incident that earlier prompted US President Barack Obama to apologize to the Afghan people. (AFP)