Union bosses who are planning strike action tonight have warned there will be "chaos" if the night tube is launched as planned next month.

A 24-hour Tube strike will start this evening (August 5) after London Underground's (LU) latest pay offer was rejected by four unions.

It is the second in a month unions have walked out in an ongoing dispute over pay and working conditions when the night tube services come into affect from September 12.

The revised offer tabled by LU, which includes a 2 per cent increase this year and £200 bonus per shift for drivers during the night tube introduction, "fails to give future guarantees over work-life balance and unsociable hours" Unite argued.

Three other unions, The Rail, Maritime and Transport union (RMT), Aslef and the Transport Salaried Staffs Association (TSSA), also rejected the pay offer.

The strike starts at 9.30pm but Transport for London (TfL) is advising all passengers to complete their journey by 6.30pm.

There will no underground trains running on Thursday and services will return to normal on Friday.

The DLR, London Overground, the bus network, tram and TfL Rail services are running throughout but are expected to be far busier than normal, and TfL has put on an extra 250 buses on key routes.

LU's said it is committed to getting the right work-life balance for staff by guaranteeing workers two days off out of seven, drivers will have the same weekends they have off now during the transition year, and after that, they will not be forced to continue working night tube shifts.

The RMT says bosses privately believe the September 12 start date is not deliverable and have called for an immediate suspension of mayor Boris Johnson's "vanity project".

A spokesman, said: "RMT says that is an open secret across the job that senior managers do not believe that the Night Tube is deliverable on the 12th September without unleashing repeated chaos.

General Secretary Mick Cash, added: "Londoner's need to be aware that the Night Tube was rushed and botched from the off and that is why five weeks before it starts staff are striking because they will not accept that their work/life balance should be wrecked to plug the gaping holes in staffing capacity that should have been dealt with from day one."

LU's chief operating officer, Steve Griffiths, has apologised ahead of the disruption.

He said: "I am sorry that the journeys of our customers will once again be disrupted by unnecessary strike action.

"After listening to the unions, we put forward an extremely fair revised offer, which makes clear commitments to support work life balance and rewards our people for their hard work.

"We urge the unions to call off the strike, put the new offer to their members and avoid further disruption to Londoners. "We remain available for talks with the unions at any time.”

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