New York - UN Secretary General Ban Ki-moon on Wednesday condemned the attack against the UN guest house in the Afghan capital Kabul, which killed at least 12 people including UN staffers, and injured a number of people.

"I am deeply shocked and outraged by the cowardly attack on a guest house in central Kabul today," Ban said in a statement.

"I condemn in the strongest possible terms the despicable and brutal killing, for which the Taliban has claimed responsibility in an apparent effort to disrupt the second round of the presidential election."

Six UN workers, including a US national, were among the dead.

Ban sent his "deepest condolences to the families and friends of the victims who were viciously killed as they sought to serve the people of Afghanistan." (dpa)