Ending a bitter seven-month standoff, Secretary of State Hillary Rodham Clinton apologized to Pakistan on Tuesday for the killing of 24 Pakistani troops last fall and won in return the reopening of critical NATO supply lines into Afghanistan. The agreement could save the U.S. hundreds of millions of dollars in war costs.

 The first trucks carrying NATO goods should move across the border on Wednesday, U.S. officials said. It could take days to ramp up supplies to pre-attack levels, but around two dozen impatient truck drivers celebrated the news in a parking lot in the southern city of Karachi by singing, dancing and drumming on empty fuel cans.

 “We are sorry for the losses suffered by the Pakistani military,” Clinton said, recounting a telephone conversation she had with Pakistani Foreign Minister Hina Rabbani Khar concerning the deaths that led Pakistan to close the supply routes. “I offered our sincere condolences to the families of the Pakistani soldiers who lost their lives. Foreign Minister Khar and I acknowledged the mistakes that resulted in the loss of Pakistani military lives.” 

 “I am pleased that Foreign Minister Khar has informed me that the ground supply lines into Afghanistan are opening,” Clinton added in her statement. It marked the first time any U.S. official formally apologized for the deaths, a step hotly debated within the Obama administration and one demanded by Pakistan before it would reopen the supply routes. 

Pakistani lawmakers also wanted Washington to halt all air strikes in the country and stop shipping weapons and ammunition to Afghanistan through Pakistani airspace, demands the U.S. has ignored. Negotiations stumbled at one point over transit fees Pakistan sought to charge.