Talks have failed to reach an agreement to avert another Tube strike over the bank holiday weekend.

Union members and London Underground managers met on Wednesday to try to settle disputes before the industrial action is due to start on Saturday.

Hugh Roberts, a regional officer for Unite, said: "Talks to resolve the London Underground pay differentials dispute involving the workers who control the power to run the Tube have been adjourned for the day and will resume tomorrow."

The union claims that the network could be “completely shut down” if workers who control the power to lines walk out.

The 40 technicians, mostly members of the union, work in the control room that provides the electricity for the 270-station network.

The strike is due to start at midnight on Saturday and last the entire weekend until 8am on Tuesday.

Transport for London is hoping to run a normal service if the strike goes ahead by replacing the employees.

According to the Unite, the “complex” dispute involves the workforce being transferred to other groups, then moved back to London Underground under different conditions.

The change sparked disputes over employees' length of service, affecting pensions and other entitlements.

Unite is also demanding more money for its members to train new recruits.

Hugh Roberts, a regional officer, said: “There is a real possibility that the Underground could close down over the bank holiday weekend.

“Unite is working very hard to achieve a fair settlement for our members – and to avoid the industrial action. The ball is very much in the management’s court.”

Tube strikes in February and at the end of April caused misery for millions of Londoners and tourists.

A bank holiday walk-out would coincide with strikes on the Heathrow Express train line from the airport to central London.

On Friday and Monday, services will run every 30 minutes rather than the usual 15 because of staff shortages.

Richard Jones, the head of command and control at London Underground, said the TSSA and RMT had also raised issues around workplace issues and conditions for the power control team.

He said London Underground was "happy to discuss£ anything not already being addressed.

Mr Jones added: "We are disappointed that the unions have chosen to call strike action and we would urge all unions involved in this dispute to continue discussions to resolve this matter."