Japanese conquest of Burma main attack westward from Rahaeng in Thailand across the Kawkareik Pass. The 16th Indian Infantry Brigade of the 17th Indian Division guarding this approach retreated hastily westward. The Japanese division advanced to Moulmein at the mouth of the Salween River which was garrisoned by the 2nd Burma Infantry Brigade. The position was almost impossible to defend, and had the River Salween, almost wide, behind it. The 2nd Burma Brigade was squeezed into a progressively tighter perimeter, and eventually retreated over the river by ferry on 31 January after abandoning a large amount of supplies and equipment. Part of the force
Malaysia–Thailand border of the common tripoint at Agreements The 1909 Anglo-Siamese Treaty states that the maritime boundary between the two countries as follows: Subsequently, the two governments signed several agreements over their common maritime boundary in the Gulf of Thailand and South China Sea. The 1973 continental shelf boundary agreement between the two governments only covered the Straits of Malacca segment and did not cover the border in the Gulf of Thailand but on 24 October 1979, an agreement and a memorandum of understanding were signed to determine the common maritime boundary of the two countries in the Gulf of Thailand. The