Presidential candidate Sean Gallagher said he "could not even begin to countenance" the return of a hard border on the island of Ireland post-Brexit.
The former Dragons' Den star said he had first-hand experience of how "very intimidating" crossing a militarised border could be and he was "very fearful" for young people should a hard border between Ireland and the North be reinstated.
"I spent my teenage (years) and early twenties travelling across the border, only miles from where I lived, spending hours at checkpoints being stopped," Mr Gallagher said.
Born in Co Monaghan in the 1960s, the businessman grew up in the small village of Ballyhaise in Co Cavan, about 10 miles from the border.
"Late at night it was precarious to cross the border," he said.
Mr Gallagher recalled that, when he was a child, his family would travel to visit his father's relatives in Donegal and the car would be stopped at the border and guns would be pointed at them.
"It becomes a normality, a normality that should not be allowed to happen," he said.
"It should never be allowed to happen again."
Mr Gallagher added that the closest politician to him growing up would have been DUP leader Arlene Foster, who lived about 20 miles from him, yet he said their lives would never have become entangled because they came from different communities.
"While geographically she was the closest, in everything else we were worlds apart," he said.
The independent candidate has promised to campaign for a united Ireland.
If elected as president, Mr Gallagher said, he would want to play an active role in achieving a united Ireland in his lifetime.
The 56-year-old candidate said the time was right to start discussions and build relationships before making a move towards unification.
It is the businessman's second bid for Áras an Uachtaráin.
In 2011, Mr Gallagher was one of seven candidates who lost out to President Michael D Higgins during the last presidential election.
The father-of-two said he had learned lessons since his last attempt to secure the office.
"I had to do some soul-searching after the last campaign," he said.
He said he spent six years locked in a legal battle with RTÉ over a tweet read out during the last live TV debate.
The tweet was purported to be from an official account linked to the late Martin McGuinness, who also ran for president in 2011.
However it later emerged the account was not the official campaign account of the Sinn Féin candidate.
Mr Gallagher said he was running for a second time because he had never shied away from a challenge.
The businessman, who lives in Delgany, Co Wicklow, with his wife Trish and two young children, Bobby and Lucy, has faced criticism for not taking part in the first presidential debate of the campaign on RTÉ last week.
President Higgins said he could not be present because of a scheduling conflict.
Mr Gallagher said he had opted out for "reasons of inclusivity".
"Out of respect to him (Mr Higgins) and of respect of the office, all candidates need to be accommodated," he said.
The entrepreneur reiterated his stance that he will only take part in debates where all candidates were present.
If elected, Mr Gallagher said he would champion the rights of people with disabilities, and introduce initiatives relating to the Irish language, wellness, and the role of women in public life.
The candidate believes an important element of the job will be the advancement of Ireland's role within Europe post-Brexit, while also maintaining the country's existing relationship with Britain.