Addressing a joint press conference with British Prime Minister Gordon Brown here, Obama vowed to defeat and dismantle the terror network across the world.
He said Washington would not allow Pakistan and Afghanistan to become a safe haven of al-Qaeda.
"The elimination of al-Qaeda was in the greater interest of both the countries," The News quoted Obama, as saying.
Earlier, Mehsud while claiming responsibility for the strike on the Police Training Academy in Lahore,warned of a attack on Washington in near future.
He also said that the attack in Lahore was in reaction to the US drone strikes in Pakistan's Tribal Areas.
Mehsud is already wanted by the United States, and it had also announced a reward of five million dollars to anyone revealing his whereabouts.