 Complete the following phrase:  The four districts of Möng Tang, Möng Hang, Möng Kyawt and Möng Hta, located to the south on the eastern bank of the Salween belonged to the Cis-Salween Sawbwa of Möngpan. In 1888 there was trouble owing to the action of the Siamese, who attempted to take possession of them. The districts were annexed by Thailand in 1942, following the 