David Cameron has arrived in Rangoon where he is meeting democracy activist Aung Sang Suu Kyi.
He has completed talks with Burmese President Thien Sein including on the release political prisoners.
A Downing Street spokesman said Mr Cameron is "cautiously optimistic for the future" and believes President Thein Sein is "sincere in what has happened so far" in terms of political reforms.
The Prime Minister said he would agree to a suspension of sanctions against Burma during a historic visit to the former colony
The democracy activist Aung San Suu Kyi lived in the UK before becoming the head of the Burmese opposition movement.
Early this morning David Cameron will set foot in a country no British Prime Minister has visited for more than six decades.