New Piccadilly line trains delayed by up to a year

The new trains will be lighter and more environmentally friendly

New Piccadilly line trains will now be introduced up to a year later than planned.

The 94 fully walk-through trains with air-conditioning and CCTV had been pencilled in for passenger use in late 2025.

Transport for London (TfL) confirmed that this was now scheduled to happen in the second half of 2026.

Testing for the trains will begin this summer, TfL said. The new-generation trains will replace the existing 1970s fleet.

The fleet will be the first on a deep Tube line to have air-conditioning

The new trains will be lighter and more environmentally friendly, with real-time displays and wider doorways. The model is being described as the "most complex" train ever to be introduced to the Tube network.

TfL said some of the engineering challenges were down to the Piccadilly line being one of the longest and deepest Tube lines.

The carriages will have 10% more capacity than the trains currently in use

The network added that the engineering complexities had been more challenging than expected, which had caused the delay to the rollout.

Siemens Mobility and TfL said it would take up to a year to test the trains, which is partly due to the tunnel infrastructure on a rail line that is nearly 120 years old.

Sambit Banerjee, Joint CEO at Siemens Mobility, said: "We're sorry we can't have our innovative trains running for passengers even sooner but, once they're in service, the technology on these new trains will bring smoother, greener and more comfortable journeys for Londoners for the next 30 or more years."