PLANS to extend all-night services to the subsurface lines of London Underground as well as the DLR and part of the Overground have been announced by the Chancellor and the Mayor of London.

All-night services at weekends on most tube lines are already set to begin in September. Trains will now run all night on the Metropolitan, Circle, District, and Hammersmith & City Lines as well once modernisation has been completed.

24-hour operation will be extended to the Highbury & Islington to New Cross Gate section of London Overground in 2017 and to the Docklands Light Railway by 2021.

The announcement came as the Chancellor and Mayor visited Victoria station overnight to meet maintenance workers.

The developments are part of a six point plan which the Treasury said is intended to add £6.4 billion to the London economy by 2030 and create over half a million extra jobs over the next five years.

In a related development, all subterranean sections of the Underground will offer Wi-Fi by the end of the next Parliament.

As part of a wide range of transport announcements in the Long Term Economic Plan for London, the government will also ask TfL to come forward with proposals for new infrastructure projects including Crossrail 2, the Bakerloo Line extension beyond Elephant & Castle, Old Oak Common redevelopment, the next phase of Underground upgrades, Lower Thames Crossing and East London river crossings. The Treasury said that this 'will ensure that new decisions on spending can be taken later this year'.

The Mayor of London also confirmed that TfL is ordering 200 more new Routemasters this year and committing to providing 800 new buses a year from 2016 onwards.

Chancellor George Osborne said: "We are today committing to provide London with £10 billion for new transport improvements. We live in a 24 hour city, and the Mayor is going to set out how our plan will deliver a 24 hour tube operation to support it. I am also asking the Mayor to think big about the capital’s long term needs.

"I want these plans and others worked up, properly costed and prioritised so we can make a decision to go ahead in the government’s Spending Round this summer."

The Mayor of London, Boris Johnson, added: "As London’s population continues to grow it is investments in infrastructure such as this which will ensure that the capital remains competitive and the best big city to live in. Today we have committed to additional night Tube services, the first 24 hour London Overground and the purchase of hundreds of brand new buses. This, combined with the promise of future investment in projects such as Crossrail 2 and the Bakerloo Line extension, will ensure we keep the capital’s economy moving well into the 21st century."

But the extensions of all-night operation will need higher staffing levels, according to the RMT.

The union's general secretary Mick Cash said: "This announcement has been dropped on London by the Mayor as a blatant pre election stunt without a shred of consultation with the union. That is a ridiculous way to conduct important negotiations and to unveil major service developments.

"RMT is not opposed to extended running but there are massive issues on staffing, safety and maintenance which have not been addressed and which would need to be signed off by our  ‎reps.

"This announcement has been made against the backdrop of a near doubling in assaults on staff, cuts to over a thousand jobs and the axeing of guards on London Overground. Night running would mean increased drunkenness and risks to both passengers and staff alike and could only work with substantial increases in staffing right across the board and that means an immediate reversal of the current cuts programme."