The train drivers' union explained that the issue would not have arisen if the operating companies had employed enough staff.

Speaking to Today on BBC Radio 4, Ms Alexander spoke on staff overtime: "It is not in the contracts of a lot of existing staff on our railways, and this varies incredibly by train operating company, to necessarily have to work on a Sunday,

"I want to have a mature conversation with the leadership of the trade unions, both Aslef and RMT, to work out how we can create a railway that is fit for the 21st century."

Ms. Alexander claimed that workers "don't feel the need to be working on the Sunday" as a result of the significant amount of money that has been deposited into their bank accounts over the last several months, which is creating issues for the entire sector.

Following a 15% wage increase from the government, train drivers are refusing to work more shifts during the holiday season.