Transport for London (TfL) subsidiary London Underground has awarded a contract valued at around £1.5bn to Siemens Mobility to design and build 94 Tube trains.

The trains will be deployed on all four Deep Tube lines in London, which are Piccadilly, Bakerloo, Central and Waterloo & City.

Delivery of the Inspiro London trains is scheduled to begin in 2023 for testing on the Piccadilly line. The first of the trains is expected to serve customers in 2024.

Once commissioned, the trains are set to enhance reliability and facilitate increased frequencies from the current 24 to 27 trains-per-hour during peak times by the end of 2026.

London Underground managing director Nigel Holness said: “The introduction of new trains on the Piccadilly line will significantly improve the journeys of millions of our customers, providing more frequent and more reliable trains for decades to come.

“Delivery of the new trains in 2023 will help address crowding on the line as London’s population continues to rise.”

“This order will mean the replacement of the 1970s Piccadilly line fleet, with delivery of the new trains in 2023, and will help address crowding on the line as London’s population continues to rise.”

In addition, the deal includes a Fleet Services Agreement for the supply of spare parts and whole life technical support to the Inspiro London trains.

The trains will a feature a standardised design regarding operations, staff training, equipment, spares and maintenance in order to help TfL maximise cost savings.

The contract will enable Siemens Mobility to move forward with its plan to build a factory in Goole, East Yorkshire, to produce and commission trains.

Modernisation of the Tube represents the Mayor of London’s Transport Strategy to make the city a greener, more accessible place.

Enhanced public transport is estimated help reduce dependence on cars and contribute to the Mayor’s target of 80% of journeys to be made using public transport, cycling or walking by 2041.