More than 50 Muslim countries have banned gay and transgender groups from attending a United Nations conference dedicated to ending Aids.

African Men for Sexual Health and Rights and Ishtar Men Who Have Sex With Men were among those denied access to the meeting, which will be held next month.

Though no official reason was given for the ban, Western officials pointed out that nearly all of the groups denied access to the event were linked to LGBT rights.

The United States has already protested the decision, with the US ambassador Samantha Power noting that the disallowed groups "appear to have been chosen for their involvement in LGBTI, transgender or youth advocacy."

Officials from the EU and Canada have also written to Mogens Lykketoft., the president of the UN general assembly, to express their displeasure.