Prime minister on Tuesday blocked conscience vote
9-1 decision stems from case challenging Campeche law
Prime minister’s ruling coalition opposes gay nuptials
Advocate: Obama a ‘great supporter of equality’
Bill expected to be introduced in Parliament on Tuesday
Event took place a year after anti-gay law struck down
Anwar Ibrahim serving five-year prison sentence
Events took place without violence
Unclear whether countries’ LGBT rights records raised
Law banning ‘aggravated homosexuality’ signed in 2014