General Micheal Casey

The U.S. army's chief of staff says he believes more troops are needed in Afghanistan.

General George Casey said in a U.S. television interview, NBC's "Meet the Press" Sunday additional forces are needed to cut the Taliban's successes and train Afghan security forces.

He did not say how many more troops should be sent to the war.

U.S. President Barack Obama has been deliberating for weeks whether to deploy 40,000 more troops to Afghanistan, as requested by General Stanley McChrystal, the commander of U.S. and NATO forces there.

Britain's military chief Jock Stirrup said Sunday Washington's delay has caused frustration in London.

He told British radio, BBC the current strategy requires more force. Without that, he said, London would have to "think again." He did not elaborate.