"An enhanced system check for door engine failures will be introduced with immediate effect . RMT reps will continue to take part in additional investigations on the failure this morning.

"The case for continued safe operation has been issued by the Chief Rolling Stock Engineer and on that basis we are supporting our members in the return to normal operation.

"RMT pays tribute to the swift action of union safety reps who once again have proved that they are the front line when it comes to safe operation of services for passengers and staff alike. The union will continue to closely monitor the safety regime across the ‎tube network. "