TALKS to prevent a fourth London Underground strike will start again on Monday.

LU has this week been trying to thrash out a deal with the RMT and TSSA unions in a bid to see off the walkout.

Thousands of Tube staff are set to begin industrial action on the evening of November 28, causing severe disruption for the Monday morning peak time the following day.

The conciliation service ACAS confirmed all sides have been in talks until yesterday, when they were adjourned until Monday.

But after three 24-hour strikes already this autumn, passengers will doubt an agreement can be reached over the long-running dispute about job cuts and staffing levels.

Indeed, tensions have only mounted this week with the unions releasing a leaked TfL document that suggested some stations are being left unstaffed on occasions already.

RMT General Secretary Bob Crow said: “Unstaffed stations are also a muggers and vandals paradise.

“The mayor has promised that there will be no unstaffed stations but his officials say not only that there will but that there already are. It’s about time they told the public the truth about their cuts plans.

“With just over a week before the next phase of strike action on the tube by TSSA and RMT members the time has now come for London Underground/TfL to pull back from these cuts plans, which would have a disastrous impact on tube safety and services, and to start talking with the unions about a long-term, secure future for the Underground network.”

TfL confirmed the existence of the memo but repeated its claim that it will try to keep all stations manned even after the planned 800 cuts in posts.

A spokesman said: “On rare occasions, at small above-ground stations, when staff are not available for short periods due to sickness or other unplanned circumstances, a station maybe left unstaffed temporarily while another member of staff is found.

“This is preferable to closing the station and causing inconvenience to passengers.”

The transport body claims previous strikes have seen around 40 per cent of services running as passengers continue to move around the capital in spite of the walkouts.