Simon Harris speaks after being confirmed as the new leader of Fine Gael, paving the way for him to become Ireland's youngest premier, in Athlone, Ireland, Sunday March 24, 2024. (PHOTO / PA VIA AP)

LONDON - Simon Harris is set to become Ireland's new prime minister, or Taoiseach, after he was confirmed on Sunday as the new leader of the governing Fine Gael party.

He is to replace Leo Varadkar, who unexpectedly announced his resignation Wednesday as party leader and Taoiseach, citing "both personal and political" reasons.

Simon Harris thanked those who elected him, saying that he will "repay that trust in hard work"

"It's the absolute honor of my life... to accept the leadership of this great party," Harris said in his first speech as the party leader, according to Sky News.

Harris, who has been the minister for further and higher education, was the only candidate to seek the party leadership after other potential competitors ruled themselves out.

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Harris thanked those who elected him, saying that he will "repay that trust in hard work."

"With blood, sweat and tears -- day in and day out -- with responsibility, with humility and with civility," he added.

"Challenges never go away -- they just change," said Harris. "But they can always be met if we cleave to those fundamental values which have served this nation well -- hope, enterprise, equality of opportunity, integrity, security," he added.

He also urged the party to "fight against populism and deliberate polarization."

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"We must and we will do this with civility, with honesty, with a determination to debate without rancour and personal demonisation," he said.

Harris, 37, will become Ireland's youngest prime minister in April when the Irish parliament, or the Dail, resumes after its Easter break. He will lead the coalition government in Dublin along with Fianna Fail and the Green Party.