An animal rights group has threatened to blockade the port of Ipswich to prevent the export of live animals.
Kent Action Against Live Animal Exports (Kale) wants the company Ferryways to stop exporting sheep.
Over the weekend, the group issued an ultimatum - ordering Ferryways to cease livestock shipments or face a blockade.
The company has issued a statement saying no live exports are planned but it has not completely ruled out further exports.
Animal welfare safeguards
Kale wants to stop the trade in live animal exports because it says the long journeys across Europe cause sheep to become distressed and dehydrated.
Angie Petro, from Kale, says "Ferryways is a legitimate target and action will be taken accordingly.
She added: "We want a maximum of eight hours imposed on journey times - by doing that it will wipe out animal exports."
The National Farmers' Union has said legislation controls the movement of animals and safeguards animal welfare.
Current rules specify a 14-hour limit of travel, with a one hour rest, followed by a second 14 hours of travel.
In April, EU farm ministers failed to agree on proposals to improve welfare conditions and cut journey times.
Live exports were halted during the UK's 2001 foot-and-mouth disease epidemic but resumed on 15 July 2002.
Kale has previously held demonstrations at the port of Dover.
Ferryways has said it has suspended live exports, but has not completely ruled out further exports.