BORIS JOHNSON must quit “posturing” and break his seven-year refusal to talk to London Underground workers, rail union RMT said yesterday.

Following Thursday’s crippling strike, the London mayor has written to Tube staff individually in a direct appeal to them to accept his proposals for all-night weekend services and new rosters.

Earlier this week he sought to undermine the credibility of Tube unions by claiming that their decisions had been taken without consultation of members.

But RMT general secretary Mick Cash responded: “This latest stunt of writing to all Tube staff just confirms that he is calling the shots on night Tube from top to bottom and doesn’t understand the fury he has unleashed across all grades, depots and lines.

“The continued refusal of the London mayor to have any direct contact with the transport unions, despite the fact that he is clearly in charge of the Tube dispute, is a ludicrous way to deal with a crisis that has developed on his watch.”