Mayor of Greater Manchester, Andy Burnham has written to the Transport Secretary urging her to make Avanti West Coast to run more trains between Manchester and London - or remove the firm's contract.
In the letter from Mr Burnham to Anne-Marie Trevelyan, he says he wants Avanti to run at least two services per hour by the end of the month - or have their contract removed.
Avanti's plans to return to an increased timetable but not until 11 December.
Andy Burnham says it should be sooner is calling for two trains by the end of October and three trains by December.
He said: "Unless this happens and is clearly communicated, train travel between our most important economic regions will continue to be chaotic, forcing people into their cars or into abandoning plans to travel entirely.
"Passengers face other challenges too. Tickets are still only being released a few days in advance, making planning for individuals and businesses impossible.
"These dreadful conditions would be unacceptable at any time but are particularly so now given the wholesale collapse of the timetable, something no other train company is experiencing at anything like this scale.
"Without this commitment, I will be unable to support a new contract for Avanti."
It is now more than six weeks since Avanti West Coast reduced services between London and Manchester to just one per hour.
An average of 10% of Avanti West Coast services between Manchester and London over the last three weeks were either cancelled or significantly late. Over the same three-week period, over a quarter of services (27 per cent) have failed to arrive on time.
Avanti West Coast's contract renewal comes up later this month.
A spokesperson for Avanti West Coast said: “We are already delivering on our commitment to increase the number of services we are running between Manchester and London, with 3 or 4 trains an hour departing Manchester Piccadilly at the key times of the day.
"We remain focused on providing a reliable train service for our customers and restoring a full timetable of three trains an hour all day between London and Manchester, in December.
“Our revised timetable, with no reliance on overtime, is also proving more reliable - in the last week, we have run 300 trains between London and Manchester, with approximately 1 in 30 of them cancelled, mainly because of short-notice sickness. That compares with 1 out of 13 trains cancelled back in mid-July.
“Nevertheless, we know that at the moment we’re not delivering the service our customers rightly expect and we apologise for the enormous frustration and inconvenience this is causing. We would like to thank our customers for their patience and understanding.”
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