Boris Johnson has said driverless trains should be a condition of a future bailout of Transport for London (TfL).

The Government gave TfL a £1.6 billion package to continue running services after a collapse in revenue in May due to the coronavirus lockdown, but that funding will run out in September.

On a visit to a site in Goole, in the East Riding of Yorkshire – where Siemens will open a rail manufacturing facility in 2023, the Prime Minister told reporters: “You can run these trains without the need for somebody to be sitting in the driver’s cab the whole time.

Let’s go to driverless trains, and let’s make that a condition of the funding settlement for Transport for London this autumn

“So what I will be saying to the London transport authority is let’s take advantage of this technological leap forward, let’s not be the prisoners of the unions any more, let’s go to driverless trains, and let’s make that a condition of the funding settlement for Transport for London this autumn.

“That’s the way forward for this country and we want to make use of the fantastic technology we’ve got and provide a better service for people in the capital and take the whole economy forward.”

The factory is being built after TfL awarded Siemens a contract to build new trains for the Piccadilly line.

Finn Brennan, organiser on London Underground for train drivers’ union Aslef, accused Mr Johnson of “talking nonsense” and claimed the lack of a regular Government grant towards TfL’s operating costs means TfL “cannot afford the signalling upgrade and other technology that would be needed for driverless trains”.

He added: “The Prime Minister’s policies are actually preventing any progress with transport in the capital.”

Mick Lynch, senior assistant general secretary of the Rail, Maritime and Transport union, said it was “outrageous” for the Prime Minister to “wheel out the dangerous nonsense of driverless trains as a condition of the emergency Covid-19 funding of Transport for London”.

He went on: “This is the sort of cheap political stunt that was a hallmark of his time as mayor and we would have hoped he would have grown up by now.”

A spokeswoman for Mayor of London Sadiq Khan said the current funding model for TfL “simply does not work in this new reality”.

She continued: “Ministers urgently need to agree a new funding model with either permanent funding from central Government or giving London more control over key taxes so we can pay for it ourselves, or a combination of both.”

During his time as mayor of London from 2008 to 2016, Mr Johnson was involved in a series of bitter disputes with trade unions in relation to London Underground services.

In 2011, Mr Johnson claimed that “virtually anybody” could drive a Tube train as he gave his support for more automation, adding: “I hope the unions will recognise that the patience of Londoners is not endless.”

There are currently no driverless trains on the Tube network.

Some trains are operated in semi-automatic mode, which means drivers still have to operate doors but they are not responsible for acceleration or braking unless problems occur.

TfL’s Docklands Light Railway does not have drivers in cabs, but uses onboard attendants who control the doors.