Signal upgrades on the Piccadilly line – which would lead to a 60% capacity increase – will not happen without government funding, Transport for London (TfL) City Planning director Alex Williams has declared.

New Piccadilly line trains have been ordered which will increase capacity on the line by 20%, but Williams called for additional investment to enable signals works to take place.

A planned upgrade of the Piccadilly line was "discontinued" following cost overruns and delays to Crossrail, TfL revealed in December 2018.

“It’s a bizarre situation where you’ve got the rolling stock but you can’t actually maximise the benefits,” Williams said at a Westminster Policy Forum.

“In terms of our prioritisation to ask the government, [first] is long term funding certainty and after that, the first project is the Piccadilly line signals.”

Other projects, including new trains for the Northern and Jubilee lines, have also been paused.

“We’ve had to make tough decisions,” Williams said. “The reality of all of these projects is we want to do all of them, we are working on all of them, but we have the money to deliver none.”

A £600M revenue loss for the period 2018/19 to 2023/24 was also confirmed due to the delay to Crossrail.

In December 2019 the transport body unveiled an updated five year plan which confirmed Crossrail delays and a “subdued” economy meant that a cautious approach was “necessary”.

Along with the new Piccadilly line trains, key aspects of the plan include completing a signalling upgrade and increasing capacity by a third on the Circle, Hammersmith & City, Metropolitan and District lines and refurbishing trains on the Central line.

At the time, TFL said: “TfL will also continue to make the case for Government investment to replace the life-expired signalling system on the Piccadilly line, which it had to pause last year owing to a lack of certainty around Government funding.

“It remains TfL’s intention to press ahead with this essential work as soon as funding is confirmed.”

The financial cost of the delays to Crossrail was also laid bare in the plan, with TfL restating that it had lost between £500M and £750M of revenue in addition to £600M highlighted in the previous year’s plan. TfL said that it has reduced the net annual cost of operations by more than £1bn since 2015/16 and is on track to deliver an operating surplus from 2022/23.

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