The maritime boundary between Indonesia and Papua New Guinea was established while Papua New Guinea was still a territory of Australia. The initial delimitation was made on 18 May 1971 between Australia and Indonesia and created a seabed boundary off the northern and southern coasts of Papua New Guinea. In 1973, the 20 nautical mile gap left by the 1971 Agreement between the southern coast and point B1, was delimited. The original seabed boundary delimited in 1971 was updated to divide their exclusive economic zones. In 1980, five years after Papua New Guinea’s independence, another maritime boundary agreement was signed which further delimited the northern frontier out to 200 nautical miles.