LONDON (Reuters) - Britain’s transport minister Chris Grayling said on Monday the government will launch an inquiry into whether rail companies breached their contracts after an overhaul of timetables triggered widespread disruption on the railways.

FILE PHOTO: Britain's Secretary of State for Transport Chris Grayling arrives in Downing Street in London, March 6, 2018. REUTERS/Peter Nicholls - RC184550A9B0

Grayling apologized to rail passengers, saying rail companies were not sufficiently prepared, and announced compensation for people affected.

A nationwide shake-up of timetables began last month but a shortage of trained drivers, late upgrades and other problems have led to repeated delays and cancellations on parts of the rail network.

Reduced timetables were rolled out on Monday in a bid to phase in the upgrades, but many trains were still late or did not run in some parts of northern England.

Grayling said there would be a review by his department into how Govia Thameslink Railway and Northern Rail had handled the situation and had put in place mitigation measures in case things went wrong.

The final report will be published by the end of the year.

The opposition Labour party said Grayling had failed in his responsibilities and should resign.

“I’m extremely sorry for the level of disruption passengers are experiencing and by members of staff caught at the sharp end,” Grayling told parliament.

Michael Fallon, a member of parliament for the ruling Conservative party and a former defense minister, attacked the government for failing to ensure a good service.

“This is now week three and this is becoming a scandal,” he said. “It really is time now that ministers got a grip of this.”