Mary Lou McDonald will become the first woman to lead Sinn Fein in modern times after no other candidate stood against her to replace Gerry Adams.

Current deputy leader Ms McDonald said that while nobody could fill the shoes of Republican veteran Mr Adams, “the news is that I brought my own”.

She added that Sinn Fein is “probably the most exemplary party when it comes to girl power at this stage in Irish politics” – a reference to the fact that the party in Northern Ireland is also led by a woman, Michelle O’Neill.

Sinn Fein’s governing council met in Belfast to formally ratify Ms McDonald, with a special conference to elect her to be held next month when Mr Adams, 69, steps down after almost 35 years at the helm.

The party was last led by a woman back in 1937, when Margaret Buckley took charge, strengthening the relations between the party and the IRA during her 13-year tenure.

Nicknamed “Marmite Mary” because she divides opinion sharply, Ms McDonald is the TD (member of the Irish Parliament) for Dublin Central and began her political life as a member of Fianna Fail, one of Ireland’s two mainstream political parties.

Some have accused her of making the switch to the more hardline party for opportunistic reasons, but she has insisted the move was about policy differences.

Mary Lou McDonald is currently the party’s deputy president (PA Wire/PA Images) (PA)

Ms McDonald said the party will aim to convince unionists that a United Ireland is the best way forward for everyone.

Addressing the Belfast meeting, Ms McDonald said she believes her leadership will mark a defining chapter in the achievement of a United Ireland.

“I believe Irish unity is the best solution for all of our people, including our unionist brothers and sisters. I know we have a job to do to convince them of that, but I know we are more than fit for that task,” she said.

She added: “Some of you have said to me ‘you have very big shoes to fill’.

“Well, the truth is that no one will ever fill Gerry Adams’s shoes. The truth is, my friends, I won’t fill Gerry’s shoes. But the news is that I brought my own. So I will fill my shoes.

“I will walk in my shoes and we together over the coming years will walk a journey that is full of opportunities, full of challenges, but I believe which marks a defining chapter in our achievement of a United Ireland and the ending of partition.

“As Gerry has said, that’s not a pipe dream, that is the road we are on.”

Ms McDonald said she grew up watching Mr Adams on the television and could never have imagined she would one day replace him as leader.

“Little was I to know at that time that I would come to know and work so closely with Gerry and the entire leadership and to have him as such a close friend,” she said.

Sinn Fein’s President, Gerry Adams, announced his retirement in November (PA)

“But I certainly never would have guessed that come 10 February 2018 that I would be the boss of him.”

Mr Adams told members that the party must devise strategies and win support for a referendum on Irish unity.

“We need to campaign for this,” he said. ”We also need to win that referendum ... don’t believe the naysayers and begrudgers who claim that a United Ireland is a pipe dream.

“It isn’t. It’s very real. It’s very achievable. We can do it.”

Mr Adams announced in November that he was stepping down as Sinn Fein President after leading the party since 1983.

Ms McDonald was educated at the private Notre Dame secondary school in the affluent Chruchtown area of Dublin before graduating from Trinity College, the University of Limerick and Dublin City University. She has been the TD for Dublin Central since 2011.

Before being elected to the Dail (Parliament) she made history by becoming Sinn Fein’s first MEP in Ireland in 2004.

She has attracted controversy on occasions, such as in 2009 when it emerged IRA memorabilia was being sold from her campaign headquarters.

Several party members took to Twitter to express their support for Ms McDonald.

Fiachra McGuinness, son of the late Martin McGuinness, tweeted a video message declaring he was ”proud and honoured“ to endorse Ms McDonald.