PAY talks between London Underground and the RMT have collapsed, and the union is preparing strike ballot papers for its 10,000 London Underground members.

Transport for London said it is now asking the conciliation service ACAS to help with the next stage of negotiations.

The union claimed that there had been no ‘significant improvement’ in its offer, which had been sent to the RMT by post before the talks began,

RMT general secretary Mick Cash said: ‘The failure of tube bosses to come up with proposals that meet the union call for serious improvements in both pay and working conditions has been the catalyst for the collapse of the talks today. That failure by the management side means we have no option but to accelerate the balloting process and escalate the dispute.

‘RMT is angry and frustrated that the company have opted to ignore the massive contribution tube staff make to this city, delivering services, including the night tube, often in difficult operational conditions.‘RMT remains available for further talks but no one should underestimate our determination to secure a pay and conditions deal that reflects the huge contribution of all London Underground staff.’

The talks had begun against a background of strained budgets at Transport for London, where fares have been frozen until next year by Mayor Sadiq Khan, and also where revenue has been lost because of the delayed opening of Crossrail.

After the RMT announced that the talks had collapsed, Transport for London said: ‘We have made an offer to our unions that we believe is fair and affordable.

‘We remain available for further discussions and have asked that ACAS help to facilitate these talks. We look forward to finding a resolution in order to provide certainty for our hardworking staff.’