There should be no delay in easing sanctions against Burma if its moves towards democracy continue, David Cameron has said.
But the Prime Minister said he wanted to see the situation for himself before backing any relaxation.
Mr Cameron is due to become the first Western leader to meet democracy activist Aung San Suu Kyi since she was elected to parliament when he visits the country on Friday.
Interviewed on BBC Radio 5 Live, the premier said he would also meet President Thein Sein and "thank him for the work that he has done" on democratic reform.
Asked if sanctions should be eased, Mr Cameron said: "If Burma moves towards democracy then we should respond in kind, and we should not be slow in doing that.
"But first I want to go and see for myself on the ground how things are going."
Some of the business delegation that has been accompanying Mr Cameron around South East Asia are due to travel to Burma. However, Downing Street has insisted the visit is purely political and the businessmen will merely be carrying out "cultural" activities.
Malaysian Prime Minister Najib Tun Razak was asked at a joint press conference with Mr Cameron in Kuala Lumpur whether he thought sanctions on Burma should now be relaxed.
Saying that he had recently visited Burma and met President Thein, he added: "I really do believe first of all that he is sincere. This has been supported by Aung San Suu Kyi's own personal remarks about him."
The premier said he was convinced the momentum to democracy was irreversible, and that view was shared by "many people" in Burma. Sanctions should be eased quickly in order to shore up the president's popularity, he added.