A boss at one of the Tube unions preparing a week of strike action on the London Underground has accused Transport for London of blocking a pay deal by taking an "absurd approach" to negotiations.
Aslef, the drivers' union, has called two 24-hour strikes on November 7 and 12 while the RMT has told its members - who include drivers, signallers and station staff - to walk out on different days between November 1 and 8.
Unless the strike threat forces concessions from TfL in talks due to take place next week, the walkouts threaten to cause chaos for passengers throughout the first week of November, with a total shutdown likely for several days.
TfL commissioner Andy Lord said Underground staff had been offered a revised deal worth an average of 4.6 per cent for 2024, with drivers, who earn far more than station staff, getting the equivalent of 4.5 per cent - reportedly taking their pay to £69,600.
This is equivalent to the 4.5 per cent increase accepted by Aslef for its members on the national railways.
But Jared Wood, the RMT's London regional organiser, said the annual round of pay talks had been derailed by TfL's "ridiculous insistence" that the traditional system of collective bargaining - which entitles all staff to the same deal - is replaced with greater pay banding, which could mean different rates for different staff.
Mr Wood told Nick Ferrari on LBC on Thursday morning: "We are fairly confident that we could sit down with London Underground and thrash out an agreement on the size of this pay award.
"But what has caused the strike action is a ridiculous insistence by London Underground that whatever award is agreed between us, they as management will take a unilateral decision on who is and who isn't eligible to receive it.
"This is an absurd approach to negotiation which no trade union could possibly agree to. We are negotiating for 10,000 members right across all grades of London Underground, and when we negotiate a deal in good faith we expect that to be applied to all of our members."
He added: "Instead of negotiating people's contractual pay with that person's trade union, they're saying that they will have a final say - they will be able to limit whatever a pay rise is. We are not going to accept that."
Just over half of the RMT's London Underground members took part in the strike ballot - 5,653 of 10,190 - with 5,515 voting yes and 121 voting no.
Aslef, which has about 2,000 London Underground members, saw a higher turnout of 67 per cent, of which 98.8 per cent voted to strike.
The revised deal is understood to be for a basic increase of 3.8 per cent plus a "flat rate" payment of £450, which is designed to provide proportionately more help to the lowest-paid Tube staff.
He denied that an "auction" for substantial pay rises had been created by the Labour government's decision to offer national rail staff 14.5 per cent in a three-year deal.
The strike will not have a direct impact on the Elizabeth line or the London Overground, though some shared stations could be forced to close.
The dispute is the latest to hit Sadiq Khan, who promised "zero days of strikes" prior to becoming mayor in 2016.
In January, he used £30m from City Hall funds to avert a week-long RMT strike that had been called for the first working week of 2024.
Aslef is angry that the 2024 pay deal, which should have been implemented in April, has yet to be finalised.
It wants London Underground to move towards the four-day week that it says is standard in other rail firms.
Aslef wants Tube drivers to work a four-day, 32-hour week.
It says the pay and conditions of Tube drivers has fallen behind those on the Elizabeth line and London Overground, where drivers work 34 hours over four days a week.
The Lizzie line and the Overground are operated by private firms, MTR and Arriva, under contract to TfL. In contrast, Tube drivers are directly employed TfL staff.
The RPI rate of inflation for February, which is the basis for Tube pay discussions, was 4.5 per cent.
Andrew Gilligan, a former special adviser on transport to former Prime Minister Boris Johnson, said efforts to "appease" the Tube unions during Sadiq Khan's eight years as mayor had led to more strikes, not fewer.
He said: "At some point, I think the unions are going to exhaust everyone's patience and somebody is going to place them with machines."
A TfL spokesman declined to comment on Mr Wood's LBC interview.