At the time of independence, the Dutch retained control over the western half of New Guinea (also known as West Irian), and permitted steps towards self-government and a declaration of independence on 1 December 1961. After negotiations with the Dutch on the incorporation of the territory into Indonesia failed, an Indonesian paratroop invasion 18 December preceded armed clashes between Indonesian and Dutch troops in 1961 and 1962. In 1962 the United States pressured the Netherlands into secret talks with Indonesia which in August 1962 produced the New York Agreement, and Indonesia assumed administrative responsibility for West Irian on 1 May 1963.