BORIS JOHNSON has “engineered” an industrial dispute over the all-night Tube plans so he can blame the unions when the new service is delayed, TSSA leader Manuel Cortes charged yesterday.

Workers are set to strike again next week in a row over pay and conditions for the night service — which was announced without consultation — unless there is a breakthrough in talks at conciliation service Acas, which resume today.

But Mr Cortes said the mayor was “playing politics” to stop a settlement and blame the unions if the service misses it September 12 start date.

He said: “This dispute is being engineered by the mayor from City Hall. He has tied the hands of his negotiating team who are unable to make a new offer without his say so.

“By allowing next week’s strike to go ahead, he will have an ideal excuse for delaying the start of the night Tube.”

A City Hall spokesman said Mr Johnson considered the current offer “very fair.”