Christian Solidarity Worldwide is calling on the Burmese authorities to ensure Sunday's elections are free and fair amid concerns over human rights in the country.
The elections are only the second to take place since Burma's fragile democratic transition.
The previous election in 2015 was won overwhelmingly by the National League for Democracy (NLD) led by Aung San Suu Kyi.
There were hopes among human rights organisations around the world that an NLD-led government would lead to improvements in protection for human rights in the country.
Instead the past five years have seen very grave setbacks, according to CSW, with regression in areas of human rights including freedom of religion or belief.
Aung San Suu Kyi's government stands accused of human rights violations, including continuing military offensives against ethnic groups involving war crimes, crimes against humanity and genocide.
CSW also has raised serious concerns regarding the disenfranchisement of an estimated two million people who are unable to vote, including the entire Rohingya people, internally displaced persons (IDPs) and refugees. Over one million people from 56 townships in ethnic areas won't be voting after Burma's Union Election Committee unilaterally decided to cancel voting.
CSW's Senior Analyst for East Asia Benedict Rogers said: "This Sunday, Burma needs a miracle. Over the past five years the country has lost many of the gains that had been made in terms of human rights and democratisation.
"We call on the Burmese authorities to ensure that Sunday's elections are free and fair, and remain seriously concerned that some two million people, primarily belonging to ethnic minorities, will be unable to vote.
"Burma must do far more to bring an end to discrimination against religious and ethnic minorities, including by repealing discriminatory legislation such as laws that limit religious conversion and interfaith marriage, and the 1982 Citizenship Law which denies the Rohingya people full citizenship rights."