THE start of all-night running on London’s Underground network is set to be delayed, it emerged yesterday, as drivers suspended strike action.

Workers have been locked in a bitter dispute over the impact of the new services on work-life balance.

White-collar union TSSA, blue-collar union RMT and engineers’ union Unite plan two 24-hour strikes from the evenings of August 25 and 27.

Documents circulated online by members of drivers’ union Aslef said that Underground managers had withdrawn duty rosters for the night service’s planned launch on September 12.

Talks at conciliation service Acas reportedly concluded with London Underground saying that they would not “impose” the new service without Aslef’s agreement.

A source claiming to be close to Aslef suggested that bosses had indicated a willingness to reduce the maximum number of extra nights drivers would be required to work.

London Mayor Boris Johnson has signalled that the launch could be delayed, but Transport for London gave mixed messages yesterday.

Bosses said they were “operationally ready” for the launch next month, with Tube chief operating officer Steve Griffiths claiming that the dispute was fuelled by “unaffordable demands” from the unions.

RMT said a work-to-rule in depots had caused delays on the District line yesterday.

“Tube bosses have tried to cover up the impact of the action short of a strike which is continuing across the network and which is hitting services hard, with the impact set to escalate,” general secretary Mick Cash said.

“RMT will be raising again today serious concerns that safety tolerances are being fudged and breached to try to keep services running, threatening passengers and staff alike.”

TSSA general secretary Manuel Cortes seemed hopeful that that the other unions could reach an agreement.

“Common sense seems to have broken out at last,” he said. “We are hopeful in this new climate that it should be possible to reach a comprehensive and fair agreement.

“This will allow for the implementation of a safe and secure night Tube which will benefit all Londoners.”