A senior White House official says U.S. President Barack Obama is calling on his national security team to revise the options for the U.S. war strategy in Afghanistan. Mr. Obama asked for the revisions during the latest review of his Afghanistan policy yesterday. The official says the President wants his advisors to determine how and when U.S. troops can hand over security responsibility to the government in Kabul. Administration officials say Mr. Obama wants to make clear to Afghan President Hamid Karzai that the U.S. commitment in Afghanistan is not open-ended. The President's call for revisions comes as the U.S. ambassador to Afghanistan, Karl Eikenberry, has expressed serious reservations about sending additional troops to the country. Officials say Eikenberry sent two classified cables to Washington last week expressing doubts about Mr. Karzai's leadership. The Afghan president has been blamed for allowing rampant corruption under his watch.