A group of cross-party MPs and members of the Northern Powerhouse Partnership (NPP) has urged the UK Government to invest £100bn into northern England’s rail and road infrastructure over the next three decades.

Some 80 MPs and peers from the NPP have sent a letter to Downing Street claiming that more funds should be used for strategic rail and road projects by 2050. According to the group, £24bn should also be invested in the High Speed 2 (HS2) rail project before it reaches Leeds and Manchester in 2032.

Northern Powerhouse Partnership vice chairman Lord Jim O’Neill said: “As someone attracted to spend some time as a minister because of the focus on the Northern Powerhouse, and being involved in the setting up of Transport for the North, getting a true state-of-the-art transport network is absolutely key.

“Affordable and quick trains connecting all key parts of the Powerhouse are vital to delivering on the goal of raising productivity both across the North, and with it, the country as a whole.”

The move comes after Transport Secretary Chris Grayling headed to Leeds Bradford Airport today to officially open the hub’s redeveloped departure lounge. Grayling has also been urged to take action to address the ongoing timetable crisis affecting Northern Rail.

Figures from an NPP report show that almost one million hours of productivity were lost to Northern businesses while delays and cancellations were taking place on the network, causing extra costs of up to £38m. The letter reads: “Northern Powerhouse Rail has the potential to increase capacity and reduce journey times but also to greatly enhance transport links that deliver transformational economic growth for our towns and cities.”

Conservative MP for Thirsk and Malton Kevin Hollinrake said: “This government has embraced the economic principles of the Northern Powerhouse to address the decades of under-investment in the North.

“We are now at a critical point – Northern Powerhouse Rail has the potential not simply to improve rail travel for commuters and families but to deliver economic growth right across the North, not simply in the core cities.

“Bringing forward the delivery date of NPR to the same time as HS2 arrives in the North could see the coming generation enjoy further education and job opportunities currently beyond young people today, and stimulate significant growth for the whole of the UK.”

Labour MP for Don Valley Caroline Flint commented: “We have seen the huge impact the recent timetable fiasco has had on the Northern Powerhouse – commuters unable to get to work, businesses losing out and childcare arrangements being disrupted.

“It is simply not good enough and needs urgent action to address the North’s outdated transport network. Investing up to £100bn in improving roads and rail is a must-have for the people of the North.”