Thailand neighbor (5)
'thailand neighbor' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for laos that I've seen before include "part of Asia" , "South-east Asian republic, capital Vientiane" , "Indo-Chinese country" , "SE Asian country" , "Mountainous state in southeastern Asia" .)
(Other definitions for burma that I've seen before include "SE Asian country" , "Rumba (anag)" , "Country whose name was changed to Myanmar in 1989" , "Union of Myanmar" , "Country no longer" .)