Ireland's first openly gay leader is to attend a Pride event in Belfast later as the city gears up for its biggest march of the year.
Northern Ireland is the only part of the UK where same-sex marriage remains outlawed after the Republic voted to change the law in a watershed 2015 referendum.
Campaigners have mounted an increasingly vocal bid to overturn the restriction north of the border and 8,000 people are due to parade through Belfast city centre later.
Taoiseach Leo Varadkar said his presence at a breakfast on Saturday morning as part of the Belfast Pride festival was not an attempt to unsettle anyone who holds a different view on same-sex marriage and conceded its introduction in Northern Ireland was the responsibility of local politicians.
It has been one of the sticking points preventing the return of a devolved power-sharing administration at Stormont, with Sinn Fein demanding the Democratic Unionists (DUP) stop blocking changes to the law.
The DUP, Prime Minister Theresa May's partners in government, has used a controversial Stormont voting mechanism to prevent the legalisation of same-sex marriage, despite most Assembly members supporting the move at the last vote.
The DUP rejects any suggestion it is homophobic, insisting it is protecting the "traditional" definition of marriage, and has called for tolerance of what are increasingly minority views.
It does not have enough members in the new Assembly to veto an equal marriage vote on its own, but there is no immediate prospect of the deeply divided administration being restored.
Mr Varadkar is not staying for the Pride parade through Belfast city centre later in the day.
A total of 8,000 people are expected to march from Custom House Square in the city centre and an estimated 15,000 additional supporters are anticipated, the Parades Commission, which rules on marches, said. Sixty bands are due to take part.
For the first time, representatives of the Police Service of Northern Ireland (PSNI) and the Garda south of the border will be marching in uniform.
A rainbow Pride flag has been raised at a UK Government building at Stormont for the first time.
The flag was raised beside Stormont House on Friday morning to mark the city's Pride festival.
LGBT+ Conservatives patron, Stuart Andrew MP, will take part in the Pride march along with thousands of local demonstrators.