Boris Johnson’s “positive” vision for Brexit has been praised by the DUP leader Arlene Foster as she said she would work with him if he became Prime Minister.

In a major boost for Mr Johnson’s leadership ambitions, Mrs Foster endorsed the “belief” and “spirit” contained in his blueprint for Brexit.

She criticised Theresa May’s Government, which needs the DUP’s votes to maintain its working majority, saying one of her biggest disappointments was the failure of ministers to “talk about the aspirations for the nation”.

She also refused to rule out backing a Canada-style deal for Brexit if an agreement could be found on avoiding a hard border in Northern Ireland.

Mrs Foster spoke to the The Telegraph ahead of Mr Johnson’s only appearance at the Conservative Party Conference, in which he will address 700 Tory voters at a fringe event in Birmingham on Tuesday.