He has made no secret of the fact he wants to take over every rail service in London -- and today the government appeared to back Boris Johnson's plans.
The Transport Secretary Patrick McCloughlin told London Tonight he had 'no objection in principal', to the Mayor of London having power over rail franchises.
He pledged his support as Mr Johnson officially opened a new route on the London overground service.
Our Political Correspondent Simon Harris has the story.
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The film had formed part of a commemoration to the Choucair family, three generations of whom died in the fire.
John Nolan, who was found with cigarettes and two lighters, suffered burns on 65% of his body after being alight for around six minutes.
Known as Pily she died in January, seven months after the disaster, having suffered a stroke.