Planned strikes on CrossCountry Trains in a long-running dispute over rostering and Sunday working have been suspended after "significant progress" in talks.
Members of the Rail, Maritime and Transport union took strike action before Christmas and were due to walk out again later this month.
RMT general secretary Mick Cash said: "The union is able to confirm that a new rostering deal has been tabled by management following long and protracted negotiations.
"After careful consideration and noting this development, the union's national executive committee has decided to suspend the planned industrial action."
Further strikes were due to be held on January 20, 21 and 28, but union members will now work as normal on those days.
A CrossCountry spokesman said: "After several meetings under the guidance of the conciliation service Acas, an agreement has been reached on all the matters raised by the RMT.
"We now look forward to ensuring our customers can reliably receive the level of service on Sundays that they would on other days."