What was one of the concessions that north vietnam received from the united states and south vietnam in the paris peace accords?

The Paris Accords was a piece treaty signed in 1973. The purpose of a treaty was to end the Vietnam War. The North Vietnam negotiating team called for the complete withdrawal of the US from Vietnam. Also they wanted the removal of Nguyen Von Thieu (the President of South Vietnam). President Nixon listed the concessions the US and South Vietnam were ready to make. One of the concessions was the recognition of the Revolutionary Government of South Vietnam as the only legitimate administration over the territory it controls. Those concessions made North Vietnam confident that they could defeat Thieu afterwards politically.