Rail services could be affected by a dispute over rest day working for train drivers.
Trade union ASLEF has balloted its driver members employed by First TransPennine Express (FTPE) over industrial action.
The ballot follows the breakdown of talks over proposals to introduce a four-day working week. ASLEF has asked for the company to introduce a 156-rest day a year agreement, which it says is in line with rival operators.
Keith Richmond, ASLEF spokesman, said it had asked members whether they were in favour of a strike, or industrial action short of a strike, such as refusing to carry out overtime.
He said such action could affect weekend services, which include trains running on routes in the Preston area.
Mr Richmond said: “Members have asked for more rest days and the company have refused, and we think provocatively, they have offered a £1,000 bounty for any train driver prepared to work as many hours as they are willing to offer.”
The ballot will finish on Friday, October 18. The train drivers earn salaries of £45,000 a year and above.
FTPE said it believed the deal it was offering was the best in the industry, as its drivers work an average of 4.2 days per seven days, with Sunday as part of the working week.
Where a four-day week is in operation at some other train operating companies, the average is four days in six, through Monday to Saturday, with Sunday then a rostered additional day.
An FTPE spokesman said: “It is extremely disappointing that ASLEF have decided to ballot FTPE drivers for industrial action. We have been negotiating for a number of months in an effort to introduce additional service flexibility through offering opportunities for our drivers to earn extra money by working additional shifts.
“We have offered five separate deals which have been discussed and agreed at a local level. ASLEF’s executive committee have failed to endorse these offers. We remain committed to exploring the potential of introducing a four-day working week and have offered at our cost to appoint an independent person to assess its feasibility. That offer, as was a member referendum, was declined by representatives.
“84 per cent of our drivers have previously volunteered to work and earn additional money on their rest days and we would encourage all drivers to vote in the upcoming ballot to ensure that opportunity is not taken away from them.”