Afghan President Hamid Karzai has told a top U.S. official he plans to step down when his current term ends in 2014.

Outgoing U.S. Defense Secretary Robert Gates shared Mr. Karzai's plans with a Senate panel Wednesday.

Gates praised Mr. Karzai for pursuing a long-term relationship with the United States even though Washington has “often not done a very good job of listening” to his concerns. Gates also said the Afghan leader understands the U.S. military strategy in Afghanistan and the importance of the U.S. role in rebuilding the war-torn country.

The testimony comes as U.S. President Barack Obama is reviewing options for withdrawing American forces ahead of next month's self-imposed deadline for starting a troop pullout.

White House spokesman Jay Carney said Wednesday the U.S. has made significant progress in Afghanistan but that Mr. Obama has yet to make a decision on how quickly to remove U.S. forces.

A bipartisan group of 27 lawmakers sent President Obama a letter Wednesday urging him to accelerate the troop pullout and hand security responsibilities to Afghan forces.

The letter says the U.S. has “largely met” its goals of destroying al-Qaida's safe haven, removing the Taliban government and chasing down those responsible for the September 11, 2001 attacks on the U.S.

Defense Secretary Gates, who is scheduled to leave office at the end of June, visited Afghanistan earlier this month. He told Afghan officials they must take more responsibility for securing their own country because the U.S. military commitment to Afghanistan is “not infinite in either time or resources.”

He also said a U.S. troop withdrawal will not be successful if the Afghan government does not increase security.

U.S. and NATO forces are scheduled to transfer security responsibilities to Afghan forces by the end of 2014.