AMNESTY International has said MLAs should 'apologise' to the LGBT community for not implementing same-sex marriage and a sexual orientation strategy.
Patrick Corrigan, Amnesty's programme director in Northern Ireland, will address an audience in Belfast City Hall on Monday morning to mark the beginning of LGBT Awareness week, to be officially launched by DUP councillor and Deputy Lord Mayor Guy Spence.
Mr Corrigan has called for the incoming Executive to deliver a sexual orientation strategy.
Mr Corrigan said: "The last Northern Ireland Executive made a commitment to the LGBT community to publish a Sexual Orientation Strategy and Action Plan.
"It should be a matter of deep embarrassment to all the parties involved in the last Executive that they failed to deliver on this."
He added: "They owe you an apology and an explanation...this must be in the Programme for Government, with a fixed timeline for delivery."
He also urged Stormont politicians to introduce same-sex marriage claiming there was a "clear majority" of "at last 58 out of 108" assembly members in favour of the move.
Mr Corrigan added: "And to those MLAs who are still determined to oppose equality, we say: vote against it if you must, but please don’t used the petition of concern to prevent rights for a minority and to block the will of the people."
A programme of events, including a community picnic and religious services, will be held until Sunday May 22 to mark LGBT Awareness week.
Jayne Robinson, LGBT hate crime advocate at The Rainbow Project, said: "Homophobic and transphobic hate crimes can have a devastating impact on victims.
"We want every LGBT person in Northern Ireland to know that there is no acceptable level of violence or intimidation which they are supposed to endure.
"It is unacceptable and we are here to help you."
