An out MP who championed equal marriage is leading the contest to become Ireland’s next Prime Minister.

Ireland’s Taoiseach Enda Kenny is set to announce his departure this week after 15 years as leader of Fine Gael.

As he is expected to confirm his departure, Minister for Social Protection Leo Varadkar has emerged as a frontrunner to replace him.

Mr Varadkar, who came out as gay ahead of the country’s equal marriage referendum in 2015, is expected to launch a leadership bid to succeed Kenny – a significant stepping stone in the formerly ultra-conservative country.

The politician has kept his personal life private until now, but went public with his partner of 18 months yesterday, likely in anticipation of a bid.

The popular young minister, 38, is already seen in the frontrunner in the race.

If he is elected, Mr Varadkar would be only the fourth openly gay head of government in recent global history. There is currently only one other gay leader in office, Luxembourg’s PM Xavier Bettel.

Mr Varadkar had a key role as Ireland went to the polls to vote on same-sex marriage, delivering a stirring speech in favour of same-sex marriage credited with helping win over undecided colleagues.

He told Parliament in an emotional speech: “This is not a Bill about ‘gay marriage’, it is about ‘equal marriage’. It is not about weakening one of the strongest institutions in society, it is about strengthening it by making it inclusive and for everyone.

“It is about removing the sense of shame, isolation and humiliation from many who feel excluded. It lets them know that Ireland is a country which believes in equality before the law for all its citizens.

“This Bill allows allow gay men and women, for the first time, to be equal citizens in their own country.

“No exceptions; no caveats; no conditions; just equal. This is not an act of generosity to a minority, rather it is an act of leadership by the majority.”

While serving as health minister, last year Mr Varadkar finally relaxed the country’s ban on men who have sex with men donating blood.

He has also hit out at US Vice President Mike Pence’s anti-LGBT views, saying Ireland should “try to engage positively with the new administration but not to the extent that it compromises our values”.