Until the last few days at least Hanoi and Peiping have taken the position that there could be no negotiations on Vietnam until US military personnel and equipment were completely withdrawn from South Vietnam. Their terms also included conditions which would amount to the virtual surrender of South Vietnam to Viet Cong control. Moscow's position had been somewhat more ambiguous. It had endorsed the Chinese and North Vietnamese requirement for withdrawal of US forces as a condition of a final settlement, but not necessarily as a condition for negotiations. All three powers, however, have insisted that US air strikes must cease before any negotiations take place.