BORIS Johnson has said he does not expect a border poll in Northern Ireland for "a very, very long time to come".
In an interview for the BBC Northern Ireland programme Spotlight – A Contested Centenary, which will be broadcast tonight, the British prime minister said that as "a proud unionist" he will celebrate the 100th anniversary of the formation of Northern Ireland this year.
Taoiseach Micheál Martin also told the programme that he felt an early border poll, which Sinn Féin has called for, would be "very explosive and divisive".
Former Taoiseach Bertie Ahern has suggested a poll could be held on the 30th anniversary of the Good Friday Agreement in 2028.
However, Mr Martin said it was not helpful to stipulate dates.
He said he "much prefers to see the meat on the bone, and for me, the meat on the bone is real engagement, real discussions, real opening up".
The Fianna Fáil leader said the Northern Ireland Protocol, which has effectively created a border in the Irish Sea, is not a danger to the constitutional position of Northern Ireland within the UK.
But he said he was concerned that "heat" generated around the protocol by its political critics has "drowned out" the voices of business people, farmers and educational institutions who can see potential advantages in the new trading arrangements.
Unionists have insisted the protocol must be scrapped and have mounted a legal challenge against it.
Mr Johnson, who negotiated the protocol, said his government is trying to "sandpaper" it into shape.
He told the programme that the EU Withdrawal Agreement had created "ludicrous barriers" to internal trade between Britain and Northern Ireland.
And he said checks on goods moving across the Irish Sea had always been intended to be light touch measures.
Mr Johnson said if Irish Sea trade checks work against the interests of the UK he will invoke a clause which allows either London or Brussels to temporarily suspend the protocol.
Spotlight – A Contested Centenary will be broadcast at 9pm on BBC One NI tonight with a live discussion on the BBC News NI website immediately afterwards.