CrossCountry train drivers are to strike in a row over the company not following agreed disciplinary and grievance processes, according to a union.

Aslef said its members would walk out on 3 October and refuse to work non-contractual overtime from 21 September because of the company’s “persistent refusal” to adhere to guidelines for disciplinary proceedings.

It comes after members of the RMT union walked out during the last August bank holiday weekend over allegations CrossCountry had failed to honour agreements on staffing, safety, and pay.

The train operator said it was “disappointed” by Aslef’s decision and remained committed to “reaching an agreement”.

CrossCountry’s network stretches across Britain from Aberdeen to Penzance and from Stansted to Cardiff. Its services connect most of the UK’s biggest cities including Birmingham, Edinburgh, Bristol, Leeds, Sheffield, Newcastle and Manchester.

Aslef’s district organiser Andy Hourigan said the dispute with the operator had been running “for some considerable time”.

“The company constantly breaks agreements, arrangements, and procedures – and it’s been brought to a head by the misuse of the grievance and discipline process,” he said.

He accused the company of “unilaterally, regularly, and conveniently” misinterpreting the union’s terms and conditions, but said the union was “open to any dialogue to resolve this situation”.

According to Aslef, more than 80% of its 632 members at CrossCountry had voted with almost 90% electing in favour of strikes, while 96% backed other forms of industrial action.

Aslef general secretary Mick Whelan said: “When we make agreements, we stick by them. This company doesn’t. That’s why we are taking strike action.

“Passengers need to know it’s the result of bad managers, acting in bad faith, that they will not be able to travel as and when they would wish.”

Shiona Rolfe, CrossCountry’s managing director, said: “We are disappointed for our passengers that Aslef has announced industrial action from Sunday 21 September and strike action on Friday 3 October.

“We remain committed to reaching an agreement with Aslef that avoids disruption for passengers, and remain available to continue talks.”