Rail passengers in Wales are being warned to expect delays when industrial action takes place this weekend.
Members of the Aslef union will go on strike following a dispute with Arriva Trains Wales over pay and working conditions.
The train company said its services will not operate on Sunday and Monday following notification from Aslef, with trains on Tuesday also likely to be disrupted as the network returned to normal.
Peter Leppard, operations director for Arriva Trains Wales, said the company regretted the major inconvenience the strike will cause to rail users.
He added: “Arriva Trains Wales’ senior management and officials from the Aslef and RMT trade unions have been in talks for many months in an attempt to reach a final agreement on pay and working conditions for train drivers.
“We are extremely disappointed that once again our generous offer has been rejected and the planned industrial action will go ahead.”
Mr Leppard said Arriva’s most recent pay offer, which would bring drivers’ salaries to £39,117 for a 35-hour, four-day average week, remained available for discussion.
He said: “This generous deal rewards the drivers for changing their working terms and conditions to allow the company to address the demand for running Sunday services.
“Arriva Trains Wales remains committed to finding a resolution to the current pay dispute with train drivers and we urge Aslef to call off their planned industrial action which, we regret, will cause major disruption and significant inconvenience to our customers.”
In a statement, Aslef said it had held two separate ballots for its 513 train driver members working for the company, and described the pay and conditions offer it had received as “unsatisfactory”.
A spokesperson said: “The first (ballot), asking if members were prepared to take part in a strike, was supported by a 70% return.
“The second, asking for views on action short of a strike, drew over 80% approval.
“The general secretary has advised the human resources director of the company of the union’s decision to take strike action because of the company’s failure to provide a satisfactory pay offer.”
Arriva Trains Wales, owned by German company Deutsche Bahn, operates throughout 244 stations and handles an average of 65,000 passenger journeys each day.