LONDON (AA) – A 48-hour UK rail strike began on Tuesday after the Rail, Maritime and Transport Union (RMT) rejected a pay offer.

About 40,000 rail workers across 14 train companies will walk out on four days this week amid freezing weather, with commuters facing significant travel disruptions, especially students having difficulty taking trains to school.

The industrial action will continue until Saturday, followed by further action from Christmas Eve (Dec. 24) until Dec. 27 and two more 48-hour strikes at the beginning of January.

Network Rail is warning passengers to travel only if absolutely necessary as cold weather, including snow, ice, and fog, continues to cause disruptions across the UK.

Network Rail bosses accused the union of “playing fast and loose with peoples’ Christmas plans.”

But RMT General Secretary Mick Lynch said: “The government is refusing to lift a finger to prevent these strikes and it is clear they want to make effective strike action illegal in Britain. We will resist that and our members, along with the entire trade union movement, will continue their campaign for a square deal for workers, decent pay increases and good working conditions.”

Network Rail made an offer of a 5% pay rise this year and a 4% pay rise in 2023, but Lynch called the deal “substandard,” and its members have refused it.

Britain is facing a fresh wave of industrial action, including by nurses, postal workers, and university lecturers, sparked by a bitter cost-of-living crisis triggered by soaring inflation and a deteriorating economy.

UK annual inflation jumped to 11.1% in October from 10.1% in September, its highest since October 1981, leading to a fall in real wages.