Christian Solidarity Worldwide has asked the UK Government to put human rights at the heart of a two-day visit by Burma's President.
President Thein Sein arrived in the UK yesterday and was due to meet Prime Minister David Cameron and Foreign Secretary William Hague.
CSW wants the Government to use the discussions to address "continuing grave violations of human rights, including freedom of religion or belief".
The visit is the first to the country by a Burmese President in decades and reflects political reforms introduced by Thein Sein's government in the past two years.
Many political prisoners have been released since he came to power and preliminary ceasefires have been agreed with most of Burma's ethnic armed resistance organisations.
CSW says there have also been improvements in freedom of expression, including greater freedom for the media and more opportunities for civil society and participation in political processes.
Significantly, pro-democracy leader Aung San Suu Kyi, who spent most of the last two decades under house arrest before being released in 2010, was elected to Parliament along with 42 members of the National League for Democracy in historic by-elections.
However, CSW warns that progress is being threatened by a campaign of hate speech and violence against Muslims, which saw two waves of violence against the Muslim Rohingya people in Arakan State in June and October last year. Thousands were killed and over 130,000 displaced.
In predominantly Christian Kachin State, over 100,000 civilians have been displaced as a result of the Burma Army's ongoing military offensive. At least 200 villages and 66 churches have been destroyed in the violence.
CSW said rape, forced labour, torture and the killing of civilians continue to be widespread.
CSW's Chief Executive Mervyn Thomas said religious intolerance and violence against Muslims had "escalated sharply" in parts of the country and that human rights violations in Kachin were "widespread and serious".
"While we welcome the positive changes which Thein Sein's government has introduced, we are deeply concerned that there is a mood of premature euphoria among some in the international community in regard to Burma and a rush to prioritise trade relations at the expense of human rights," he said.
"We urge the Prime Minister and the Foreign Secretary to ensure that human rights concerns are at the heart of discussions with Thein Sein and to deliver clear messages regarding the need to stop the spread of religious and ethnic hatred, intolerance and violence, to ensure release of all remaining political prisoners and to facilitate constitutional reform.
"If these benchmarks are not met before the next elections in Burma, due in 2015, there should be consequences for the Government of Burma and its relations with the international community, and Britain must make that clear."