In Paris, the peace negotiations continued, but this time, both sides were willing to make concessions. The chief American negotiator, Henry Kissinger, offered a ceasefire, recognition of the Provisional Revolutionary Government of the Republic of South Vietnam by the Saigon government, and the total American withdrawal from South Vietnam as incentives. The terms were enough to meet the criteria for victory that Hanoi's leaders had established before the offensive. The only obstacle to a settlement was Nguyễn Văn Thiệu, whose government would have to assent to any agreement. The intransigence of Thiệu and his demand for the U.S. not to abandon his nation after any agreement, as well as new demands by Hanoi, caused the stalling of peace talks in December. That led Nixon to launch Operation Linebacker II, a bombing campaign aimed at North Vietnam's transport network, especially around Hanoi and Haiphong. The Paris Peace Accords, signed in January 1973, confirmed that North Vietnamese troops would remain in South Vietnam in the areas that they occupied.