Singapore–Vietnam relations refer to the bilateral relations between the Republic of Singapore and the Socialist Republic of Vietnam. Singapore and Vietnam started the trade relations in the 19th century. Since the anti-communist policy of Singapore, Singapore supported South Vietnam before the unification of Vietnam. Singapore also started formal diplomatic relations with North Vietnam on August 1, 1973. After the unification of Vietnam, Singapore started to improve its relations with the Socialist Republic of Vietnam. The relations was worsened during the Cambodian–Vietnamese War, but it has now revived after the People's Army of Vietnam withdrawal from Cambodia.