WASHINGTON, Feb 26 — President Barack Obama yesterday backed steps by NATO's commander in Afghanistan to protect US service members there after the killing of two US officers in the Interior Ministry, and welcomed President Hamid Karzai’s call for calm, the White House said.

Obama spoke to US General John Allen after NATO withdrew all staff working in Afghan ministries following the attack, which came amid violent protests against the burning of copies of the Koran at a NATO military base near Kabul.

“We welcome President Karzai’s statement this morning encouraging peaceful expressions, and his call for dialogue and calm,” the White House said in a statement. “The United States remains committed to a partnership with the government and people of Afghanistan.” — Reuters