No leadership challenge - Johnson

Speculation of a challenge to Mr Brown in the wake of the Crewe and Nantwich by-election dominated Sunday newspapers, with suggestions he had lost support of his Cabinet.

Mr Johnson, who had been widely tipped as a potential successor, ruled himself out but conceded that the Government needed to take some short-term decisions.

"The whole issue of the leadership is settled," he told BBC One's Andrew Marr Show.

"There is absolutely no appetite I believe in the party to change the leader. Gordon Brown was the towering figure a year ago and is the towering figure in the party now. You are probably right that we need to focus on perhaps four or five issues that need to be tackled in the near and mid-term. But the long-term is important."

The Prime Minister has focused very strongly in his public statements on the fact that he is taking the "long-term decisions" required in the national interest.

Mr Johnson said the Government was going through some "really rocky times" but insisted Mr Brown was the right leader to turn it round and urged MPs to concentrate on tackling the Tory threat. "We were very good at dealing with the good times. Indeed, we created those good times. We are going through some really rocky times at the moment," he said.

Whoever was in charge would be facing a number of outside difficulties such as the global credit crunch, rising oil prices and a resurgent opposition, he pointed out. "The question is how they deal with those issues and how we, as a party, help our leader deal with those issues," Mr Johnson said.

Mr Johnson dismissed reports Foreign Secretary David Miliband was preparing the ground for a possible leadership bid if Mr Brown's position became untenable. "I know David very well. I am absolutely certain he is not manoeuvring and I know him better than the journalists," he said.

Asked about another suggestion that the PM could be forced into naming a deputy to ensure a successor was easily available, he said he would not accept such a position. "I would say no. But it's never going to happen."