A Suffolk haulage boss said industrial action at the Port of Felixstowe cost him £70,000 in just eight days.
Adam Searle, managing director of CP Transport, said: "The were no vessels arriving with cargo so the days we were working were a waste of time.
"I had to pay drivers' wages, office overheads, insurance and tax but I had no incomings.
"In total, it cost me around £70,000."
Mr Searle said his concern was for other businesses that rely heavily on the port's services.
"There was a real financial impact on transport, warehousing and distribution companies.
"If it cost me £70,000 then I can only imagine the impact it's had on other businesses."
Due to the industrial action being announced weeks in advance, Mr Searle said damage to supply chains was minimal.
However, warnings of further strikes means firms could see even greater damage.
"We're nowhere near 100% capacity yet so a number of perishable goods came in via other ports.
"But I am concerned about further strikes.
"It's the unknown that really worries me."
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