Scottish leader John Swinney has declared that Andy Burnham will be the final prime minister of the United Kingdom.
The First Minister predicted Scots would choose to exit the union if another independence referendum takes place.
The SNP leader said: "The people of Scotland, if given the choice of independence in a referendum, will take that choice, because all of the information that we see in front of us about the trends in opinion polling indicate that’s the preference of the people of Scotland."
His comments come after leaders of the SNP, Plaid Cymru and Sinn Féin signed a joint agreement stating that "Westminster’s time is coming to an end", placing renewed pressure on Downing Street to permit referendums on independence.
The first ministers of the UK’s three devolved nations – including Mr Swinney, Plaid Cymru leader Rhun ap Iorwerth and Sinn Féin vice president Michelle O’Neill – signed the memorandum of understanding in Cardiff on Monday morning.
Together with Sinn Féin president Mary Lou McDonald, who is leader of the opposition in the Irish Dáil, the group called on the Government to "prepare for, plan and facilitate constitutional change".
Meanwhile, Ms O’Neill said Donald Trump’s comments in support of Irish unity show the debate is “very much alive.”
At the weekend, the US President expressed his support for Irish unification.
“I think that tells us where we’re at with where the thinking is around what is the big prize here for our people, and the big prize here is unification.
“It is the end of partition and it is that new beginning in a new Ireland,” she said.
The group, who met in their capacity as party leaders – rather than as officials in their respective governments, stated their ambitions for partnership around the economy, energy and international co-operation.
The agreement says: “The political landscape across these islands is changing.
“For the first time ever, people across these islands have first ministers in Scotland, in Wales and in the North of Ireland who are all committed to independence from the United Kingdom.
“For people watching across these islands – for people watching around the world – there could be no clearer sign that Westminster’s time is coming to an end.
“We believe there is a better way: nations working together as equals, sharing ideas and expertise, and building relationships based on mutual respect and common interests.
“Momentum is behind our movements; we believe that constitutional change is coming.
“We therefore commit to strengthening cooperation between our parties and identifying practical areas where working together can make a real difference.”
The agreement sets out plans to “reject Whitehall’s broken economic model” and share ideas on economic growth, expand energy resources, and states that “the future of our nations belongs in the European Union”.
The leaders add: “Our nations have the right to self-determination. No Westminster government has the right to block democracy or undermine the principle that our people will decide their own future.
“We recognise that our parties have different constitutional positions and that each nation will determine its own future in its own way and in its own time.
“We call for the British Government to prepare for, plan and facilitate constitutional change in each jurisdiction.”
Following the meeting, Downing Street said Andy Burnham believes strongly in the United Kingdom and is focused on easing the cost-of-living crisis for households across the country rather than on “constitutional debates.”
The Prime Minister’s official spokesman said: “The Prime Minister is committed to delivering change across all four nations of the United Kingdom and believes strongly in the Union.
“The United Kingdom is at its best when people come together around our shared values and problem-solving, rather than division, and the Prime Minister will continue to ease pressures on household finances, and delivering greater economic security, rather than engaging in constitutional debates or further referendums.”
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