Business leaders have warned that rail services across the north of England could “collapse into utter chaos” unless the government pushes urgently for a resolution to months of disruption.

Rail services are already recording historic levels of cancellations, and the imminent introduction of a new timetable could lead to a “crisis”, the Northern Powerhouse Partnership (NPP), which represents industry in the north of England, has warned in a letter to the UK transport secretary, Mark Harper.

The call for urgent government intervention in the privately run rail services was led by the NPP’s vice-chairs, the former Siemens UK chief executive Jürgen Maier and Jim O’Neill, the former chief economist at investment bank Goldman Sachs, who is among the possible bidders for Manchester United football club. The lobby group is chaired by the former chancellor George Osborne to push for economic development in the north of England.

Maier said the disruption was costing travellers and companies dearly in lost time and business, with corporate events and associated businesses such as hotels and restaurants particularly affected.

“We’re saying: government, you really need to put pressure on and make sure you resolve this issue and get business going again before we have a miserable Christmas,” Maier told BBC radio on Monday.

“The whole timetable is going to fall to pieces, and there’s going to be even more cancellations, and people won’t be able to rely on these important services,” he said. “We are not able to continue as we are. If we do not get approval for a rest day working agreement to be negotiated this week it will be too late.”

The proportion of cancelled services in Great Britain has more than doubled since 2015, rising to one in 26 of all train journeys being disrupted in the year to 15 October, according to an analysis this month by the Observer of figures from the Office of Rail and Road (ORR). Services have also been disrupted by a wave of strikes, with more due to take place over Christmas unless unions can reach agreements with the government.

The NPP said there were already more cancellations across the north of England on TransPennine Express than after the May 2018 crisis, when the introduction of a new timetable led to the cancellation of thousands of trains over weeks of disruption. That has raised concerns about an even worse impact this time around, when a new timetable with increased services comes in on 11 December.

TransPennine Express does not have a rest day working agreement with unions, meaning it is unlikely to be able to fill its schedules when the timetable changes. However, it requires government approval to reach an agreement.

Henri Murison, the NPP’s chief executive, said there would be “real trouble” if Harper did not push for a rapid agreement. He said Harper should treat the urgent short-term issue separately to large-scale planned reforms to how the railways operate.

“We’re not prepared to wait for some grand solution,” he said. “We need a sticking plaster. We aren’t going to be some guinea pig for some grand reform.”

Chris Woodroofe, Manchester airport’s managing director, said: “Anyone travelling to catch a flight needs to know they will get there on time, but the current situation is significantly undermining people’s confidence in choosing rail as the best way to get to the airport. This is completely unacceptable and government must work with train operators to resolve the issue as soon as possible.”

TransPennine Express and the Avanti West Coast main line, which is stuggling with an over-reliance on rest-day workers, are both majority-owned by First Group, an £800m company listed on the London Stock Exchange. The Avanti disruption has meant that services between London and Manchester are running only once an hour, compared with the usual three times an hour.

In a statement to the BBC, which first reported on the NPP’s letter, TransPennine said: “We are sorry to anyone who has been affected by this ongoing disruption. This has been caused by high levels of train crew sickness, an intensive crew training programme (which includes a training backlog as a direct result of Covid), and infrastructure issues outside of our control.”