Church leaders are calling on the UK Government to use diplomacy to support the restoration of democracy in Myanmar.
State Counsellor Aung San Suu Kyi and democratically elected leaders were placed under house arrest in a military coup last week.
The military is now in charge of the country and has declared a year-long state of emergency.
Moderator of the Church's General Assembly, Dr Martin Fair, and the Moderator of the Presbyterian Church of Ireland (PCI), Dr David Bruce, are calling on Foreign Secretary Dominic Raab to take action.
In a joint letter, they write that the UK should take a leading role in building an international diplomatic response owing to its strong historical bonds with Myanmar - which was under British rule until 1948.
They urge Raab to intervene to ensure that the result of last November's election is "fully respected".
The National League for Democracy, Suu Kyi's party, won by a landslide.
"Our shock at the news of the military coup on the first of February was all the sharper because of our concern for our friends in PCM (Presbyterian Church in Myanmar) and the implications of the takeover by General Min Aung Hlaing," the letter reads.
"Myanmar suffered 49 years of brutal military rule that ended as recently as 2011.
"In the past decade people have enjoyed increasing freedoms, some political progress and increased, if imperfect, economic growth.
"The fate of the Rohingya people shows that not all in Myanmar are treated equally."