London is on tenterhooks as the tube unions involved in the Night Tube dispute are expected to give a final decision over their planned strike action on the Underground over pay and work conditions. The RMT, TSSA and Unite are expected to "review" their position after talks with management at mitigation service Acas conclude today (24 August).

The unions are set to walkout on 25 and 27 August for 24 hours in protest over LU's new Night Tube service. But sources on both sides of the dispute have told IBTimes UK that talks have been "constructive" and "positive", giving hope to millions of commuters in the capital that the sides can come to a last minute resolution.

Meanwhile, tube drivers' union Aslef is not expected to take part in the walkout. A union source has told IBTimes UK that the organisation is "optimistic" that it can secure a deal over their work roster dispute with Underground bosses. But if talks do breakdown, the union could call industrial action.

The planned walkouts threaten to cause travel misery for workers across London and could cost the economy millions in lost productivity. The dispute could also derail LU's plan to launch the Night Tube on 12 September. However, the company has maintained that it is still "operationally ready" to roll-out the service, but management stressed that it would not be "at any cost".

Baptism of fire

Whatever the outcome, the dispute has been a baptism of fire for new LU chief operating officer Steve Griffiths. The former Virgin Atlantic executive only joined the company in May and has led LU's negotiating team at Acas during the talks.

Griffith has argued that LU's offer of an averaged 2% pay rise for Night Tube staff, a £500 bonus for Night Tube workers and an additional £200 per Night Tube shift for drivers is a "fair deal". But Unite negotiator Hugh Roberts has told IBTimes UK that he wanted a salary settlement of 2.5% for all Night Tube employees, arguing the hike would be in line with other rail settlements.

Griffiths said: "Having previously argued that it was all about 'work-life balance', certain unions have now made a whole series of unaffordable demands for more pay, shorter working hours and the reversal of the modernisation of the Tube.

"The £1.4bn cost would either mean our customers being hit with an extra 6.5% fares increase on top of the annual increases already assumed or wholesale cuts for plans to modernise the Circle, District, Hammersmith and City and Metropolitan lines.

"No responsible management could even contemplate such demands. Our customers and London's businesses want to see this dispute resolved and, instead of threatening strikes, we call on the unions to engage in calm and realistic discussion with us to achieve that."

LU have said that some tube services may run during the two 24-hour-long walkouts. A Transport for London (TfL) spokesperson said: "Staff on the bus network, DLR, London Overground, TfL Rail, tram, Emirates Air Line and River services will not be on strike," a TfL spokesperson said

"These services will operate as normal but they will be much busier than usual, especially during peak hours, between Tuesday 25 and Friday 28 August. Roads and National Rail services and terminals will also be much busier. We will run whatever Tube services we can on those four days, based on the staff that sign into their shifts. All customers are advised to allow more time for their journeys."

But even with Aslef not expecting to walkout, a union source has told IBTimes UK that some of its tube driver members may decide not to across the planned RMT, TSSA and Unite picket lines out of solidarity with the unions.