WASHINGTON, May 14 (Xinhua) -- The U.S. State Department on Monday condemned the assassination of a prominent member of the Afghan High Peace Council, who has been helping the peace negotiation between the Taliban and the Afghan government.

    "The United States strongly condemns the assassination of Afghan High Peace Council member Arsala Rahmani," department spokeswoman Victoria Nuland said at a briefing.

    "The High Peace Council has been working for a durable and long- term peace in Afghanistan, and those who attack members of the Peace Council are out of step with the Afghan people," she told reporters.

    Arsala Rahmani, a former high-ranking Taliban official and a member of the Afghan High Peace Council, was assassinated by a gunman on Sunday. The killing dealt a blow to the political reconciliation effort aimed at ending the decade-long war in the war-torn country.

    It was the second killing of a prominent member of the government-appointed peace council. In September 2011, former Afghan President Burhanuddin Rabbani, the former head of the council, was killed in a suicide bombing in Kabul.

    Nuland stressed that the United States remained committed to fostering an "Afghan-Afghan process of reconciliation."

    "It's the Taliban who have put a pause on the talks, as Ambassador Grossman and others have made clear," she noted.