Port of Felixstowe bosses and union leaders reached a deadlock in talks to avert strike action last night.
Officials were unable to reach a conclusion in arbitrations meetings on Monday after the port's Unite members voted in favour of industrial action by a majority of 92%, following a pay dispute.
Talks are set to resume on Thursday.
Felixstowe Dock and Railway Company had offered a pay increase of 5% to its workers, but union bosses said this was "fairly far away" from their demands and an effective pay cut with RPI currently standing at 11.9%.
If strike action does go ahead it is expected to take place towards the end of August.
Business leaders and the government have called for a negotiated solution as a walkout at Felixstowe, the UK's largest port, could see vessels be diverted elsewhere in the UK or Europe.
Chris Starkie, New Anglia LEP chief executive, warned: "Felixstowe Port plays a critical role in keeping goods moving in our region, and this and other planned industrial action promises to cause major disruption to the supply chain, local businesses and consumers.
"I would urge businesses to start making contingency plans now."
This latest dispute follows more strikes in recent days.
Yesterday and on Friday, BT and Openreach workers formed picket lines around the county and walked out as part of a dispute over pay.
Members of the Communication Workers Union (CWU) formed picket lines outside Adastral Park in Martlesham and outside an Openreach centre in Bury St Edmunds.
The CWU said it was the first national telecoms strike since 1987 and the biggest ever among call centre workers. Union members voted in favour of industrial action in protest at a £1,500 pay rise.
On Saturday, train drivers at Greater Anglia walked out again for 24 hours as part of a pay dispute between the Aslef union and train companies.
Further strikes are planned this month by Aslef and the RMT, as they remain deadlocked in a row over pay, jobs and conditions on the railways.
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