About 1,900 members of the union Unite are taking strike action, expected to last eight days, at the Port of Felixstowe in Suffolk, from Sunday.

The union said members rejected a 7% pay offer from port operator, the Felixstowe Dock and Railway Company, which it said was “significantly below” the rate of inflation.

A port spokesman described the union decision to strike as “disappointing”.

A picket line formed early on Sunday as the strike began, and the union said it would be manned until 22:00 each day of the strike.

About 2,550 people work at the Port of Felixstowe, which handles about 48% of the UK’s container trade.

Ahead of the strike, port spokesman Paul Davey said workers had been offered 7% plus a single payment of £500.

He said the offer represented “an increase of between 8.1% and 9.6%, depending upon the category of worker at the port”, at a time when the average pay increase in the country was 5%.

“We’ve got a shrinking economy, we’re going into recession – as a country I think that’s a very fair offer indeed,” he said.

Freight transport body Logistics UK said it was “not expecting massive disruption” from the strike action at the port.

A spokesperson for the trade association told BBC News: “Felixstowe is not a just-in-time delivery port – everything coming in is scheduled well in advance.

“If it [the strike] goes on for longer than eight days then those using the port will be looking at alternative routes, but at the moment there is plenty of stock in the supply chain. Others have already been planning alternative routes – we’re not expecting panic.”

The spokesperson added: “As an industry, we are incredibly flexible and have been working for a while to put these goods into alternative ports if they have to be.”

But PA press agency’s industrial correspondent Alan Jones described the action as unprecedented.

“Dock strikes are as big as it gets really because of the importance of goods coming in,” he told the BBC.

“A lot of companies have suffered a shortage of goods anyway, partly because of Brexit and the pandemic, so this really is going to cause a lot of problems.

“Felixstowe has been strike-free for about 30 years.”

Derek Hailstone, co-owner of Mick’s Cycles, in Bury St Edmunds, Suffolk, says the majority of his stock comes in through Felixstowe.

“The strikes have the potential to affect us, as most of our stock comes into the UK through Felixstowe,” he says.

Haulage company Turners of Soham, in Cambridgeshire, moves about 500 containers out of the port every day.

“About 30% of our business is at Felixstowe, so it’s going to have a huge impact,” says Paul Day, managing director.

Unite general secretary Sharon Graham said: “Felixstowe docks is enormously profitable.”

Together with its parent company, CK Hutchison Holdings Ltd, they could “give Felixstowe workers a decent pay raise”, she said.

“It’s clear both companies have prioritised delivering multi-million pound profits and dividends rather than paying their workers a decent wage.”

Strike action at the port is expected to last until Monday 29 August.

The port said its staff union, which represents about 500 clerical and engineering employees, had “voted to accept the same pay offer that Unite has refused to put to its members”.

Unite said it balloted the dock workers, not the clerical groups represented by the The Port of Felixstowe staff union.

Referring to the staff who had accepted the offer, a Unite spokesperson said: “This group of members have the right to accept the offer from the company but Unite’s dockers want to press for 10%.”