Avanti West Coast train managers have voted to strike for three days over the Christmas period.

The RMT union said that walkouts have been scheduled for 22, 23 and 29 December for the London to Scotland service after rejecting the train company’s proposals for “rest day working arrangements”.

Train managers usually work a four-day week but due to staff shortages can be asked to work on rest days but the RMT said that the current arrangements are “unacceptable”.

A spokesperson for Avanti West Coast said that at “one of our busiest and most important times of the year” customers “will now face significant disruption because of these strikes”.

The strikes have been announced just weeks after the RMT accepted a backdated pay rise of 5% from the Rail Delivery Group, the body which represents train companies.

But a dispute remained over planned changes to working practices and talks over future pay.

RMT general secretary Mick Lynch said: “Train managers are being treated unfairly compared to senior managers, who receive significant payments for covering these roles.

“Our members have had enough and this strike action demonstrates their determination to win a fair deal.”

Avanti West Coast said: “We are disappointed the RMT have voted to decline the very reasonable offer made to them to resolve the rest day working dispute and prevent inconvenience to those many people who will be travelling on the West Coast Main Line over this time.

“We will continue to work with the RMT to resolve the dispute.”

Mr Lynch said the union remains ready to reach a settlement, adding: “We urge management to show they are serious about resolving this dispute.”