A Canada-style trade deal with the European Union after Brexit would be worse than a ‘no deal’ because it would break up the UK, Theresa May has said.

The Prime Minister made clear her face is implacably set against a deal based on Canada’s trade agreement with the EU which was offered by Brussels in the spring.

Mrs May’s concern with a Canada-style trade deal is that it would mean the UK has to have a border in the Irish Sea to avoid a hard border on the island of Ireland.

Asked whether a “no deal is better than Canada plus” on a flight en route to New York City where she will address the United Nation’s general assembly, Mrs May said: “I have always said that no deal is better than a bad deal.

“A bad deal for example would be one that broke up the United Kingdom - we want to maintain the unity of the United Kingdom.

“What we have put on the table is a good deal - it is a deal which retains the union of the United Kingdom, our constitutional integrity.

“It is a deal which provides for no hard border between Northern Ireland and Ireland, protects jobs and enables us to have a good trading relationship with Europea and the rest of the world.”