The first day of a planned strike at Britain’s biggest container port started Sunday, joining a series of walkouts by transportation workers that have disrupted economic activity across the country.

Almost 2,000 workers at the Port of Felixstowe, located about 150 kilometers (93 miles) northeast of London, walked off the jobs over pay, raising fears of severe supply chain problems. The port handles around 4 million containers a year from 2,000 ships – almost half of the country’s incoming shipping freight.

Sharon Graham, general secretary of Unite, the labor union that called for the strike, alleged the company that operates the “enormously profitable” dock and its parent company, C.K Hutchison Holding Ltd, prioritized shareholder profits over worker welfare.

“They can give Felixstowe workers a decent pay raise. It’s clear both companies have prioritized delivering multimillion-pound profits and dividends rather than paying their workers a decent wage,” she said.

The Port of Felixstowe said in a statement that it regretted the impact the strikes would have on U.K supply chains. It said workers were offered a pay raise “worth over 8% on average in the current year.”

Britons are facing the worst cost of living crisis in decades as wages fail to keep pace with inflation and grocery costs and utility bills increase. The latest statistics put the inflation rate at 10.1%, a 40-year high.

The conditions have sparked summer strikes by train and subway workers following the breakdown of wage talks in June. Only one in five U.K trains ran Saturday during the third railway strike in as many days.

On Friday, many of London’s underground subway lines did not run due to a separate strike. Postal workers, lawyers, British Telecom staff and garbage collectors have all announced walkouts for later this month.