Updated

The United States is reimbursing Pakistan $688 million for the cost of providing support for some 140,000 troops on the border with Afghanistan.

Deputy Defense Secretary Ashton Carter notified Congress in a letter earlier this month. Carter wrote that the reimbursement is consistent with the national security interests of the United States.

Members of Congress have railed about aid to Pakistan, with extreme frustration with Islamabad after the killing of Osama bin Laden in Pakistan. This past July, the relationship improved slightly with the opening of supply lines into Afghanistan.

The money covers expenses from June through November 2011.