Leo Varadkar is on course to become only the fourth openly gay world leader in modern history.

The race is underway to replace Ireland’s Taoiseach (Prime Minister) Enda Kenny, who announced his departure earlier this year after 15 years as leader of Fine Gael.

Leadership contender Leo Varadkar is the hot favourite to replace him as both party leader and head of government, maintaining a strong lead over his only remaining rival, Simon Coveney.

Mr Varadkar, currently the Minister for Social Protection, would be only the fourth openly gay head of government in recent global history if elected.

There is only one other openly gay leader currently in office, Luxembourg’s PM Xavier Bettel.

Mr Varadkar already has a strong lead among the Fine Gael Parliamentary party, which holds the majority of the votes in the party’s complex electoral process.

He said: “It’s started really well and I’m really humbled at the level of support I have received from my colleagues, but I’m not counting my chickens.

“I’m really looking forward to the hustings and the debates.”

The new Fine Gael leader will be elected by an electoral college comprised of members of the parliamentary party (who have 65% of the vote), local councillors (10% of the vote) and regular party members (25% of the vote) on June 2.

Ahead of the race, the politician went public with his partner of 18 months. His boyfriend, doctor Matt Barrett. would likely gain a public profile as the leader’s partner if Mr Varadkar is elected.

It has been a steep climb for the 38-year-old, who only came out as gay in 2015, ahead of the country’s equal marriage referendum.

He said: “It’s not something that defines me. I’m not a half-Indian politician, or a doctor politician or a gay politician for that matter. It’s just part of who I am, it doesn’t define me, it is part of my character I suppose.”

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”.