Britain will no longer discourage trade with Burma, William Hague announced today, in recognition of the “remarkable changes” that are taking place there.
The Foreign Secretary said the country was now on "a hopeful path" and that "responsible" trade and investment could help the reform process.
Britain is planning to open a diplomatic office in the new capital, Naypyitaw, he said.
The announcement comes after the EU backed UK calls for the suspension of sanctions against Burma. David Cameron this month became the first serving prime minister to visit the country, which became independent from Britain in 1948.
The formerly isolated nation has helped thaw relations with the West by releasing political prisoners and holding parliamentary by-elections, which this month that saw opposition leader Aung San Suu Kyi's opposition party win 43 seats.
Mr Hague said today there were "remarkable changes finally taking place in Burma" after years of pressure for political and human rights reform.
"We still have concerns about Burma's ethnic conflicts and about human rights, including remaining political prisoners," he said in a speech in Singapore.
"But we welcome the boldness shown by President Thein Sein and by Daw Aung San Suu Kyi herself which has finally placed the country on a hopeful path, as well as the efforts by several ASEAN (Association of South East Asian Nations) members over many years."
Ms Suu Kyi has been invited by Mr Cameron to visit Britain in June. It would be the first time she has left Burma in more than 20 years and presents a major test for the government's commitment to reform.
"Today, after discussion with Aung San Suu Kyi and very careful consideration, I can announce that the British Government will lift its policy of discouraging trade with Burma," Mr Hague said.
"We believe that at this moment in time the right kind of responsible trade and investment can help aid the country's transition.
"We will put responsible investment at the heart of our future commercial relationship with Burma, encouraging investment that will benefit local communities and respect the local environment."