A victory for Boris Johnson at the next election would be a "disaster" and speed up the break up of the UK, a former Tory chairman has said.
Lord Patten accused the Prime Minister of leading an "English Nationalist Government", which he said voters "can't trust".
The Conservative peer, who was a Cabinet Minister under Margaret Thatcher, said another win at the polls for Mr Johnson would be destructive for the party and for the union.
