Workers at Britain’s biggest container port Felixstowe plan to stage a second eight-day strike over pay, adding to a wave of industrial unrest caused by soaring inflation.

Fresh strikes are planned from September 27 to October 5 after port workers voted by an 82 per cent majority to reject a 7 per cent pay offer, Unite said.

"Further strike action will inevitably lead to delays and disruption to the UK's supply chain," Unite national officer for docks Bobby Morton said, referring to port operator CK Hutchison.

"This is entirely of the company's own making."

With inflation having topped 10 per cent in July and projected by the Bank of England to exceed 13% next month, Unite says the 7% pay offer represents a "real terms pay cut."

"The collective bargaining process has been exhausted and there is no prospect of agreement being reached with the union," Felixstowe port said.

It added port authorities were "very disappointed" with news of the strike and were implementing the 7 per cent pay award plus £500 ($585) backdated to January 1, 2022.

The strike would follow a similar eight-day walkout at Felixstowe port last month, which clogged supply lines but fell short of causing widespread disruption in an industry already facing supply chain issues.

Elsewhere in Britain, more than 560 dockworkers at the Port of Liverpool, one of the country’s largest container docks, are set to go on strike from September 19 to October 3 over pay.

About 48 per cent of all containers brought into the UK are transported through the Felixstowe port, according to Unite, making it an important import hub for Britain.

Another strike at Felixstowe would be the latest in a wave of industrial unrest across Britain this summer that has affected a range of industries, from aviation and transport to nurses and lawyers.

However, some unions in recent days have suspended plans for industrial action in light of Britain’s 10-day mourning period following the death of Queen Elizabeth.