Unions were asking port workers salaries to be raised between 3,250 rupees and a maximum of 9,000 rupees.
"It will take awhile to clear the backlog. But the damage to reputation, loss of business, on top of demurrages paid runs into millions," Perera said.
He said around 16 ships bypassed the port of Colombo during the work-to-rule period and estimated the loss of revenue to be in the region of 20 million rupees each day.