The import of European mineral water and several food products into Britain could be restricted under retaliatory measures being considered by ministers over Brussels' refusal to end its blockade on UK shellfish.
The Telegraph can disclose that ministers are looking at proposals dubbed "Water Wars" which could see the UK end a number of continuity arrangements it has agreed with the EU.
Senior Government sources pointed to potential restrictions on the import of mineral water and seed potatoes, the latter of which the EU has secured a temporary agreement on until the end of June.
In a warning shot to Brussels, a Government source said: “There is thought being given to where we can leverage in other areas. We have continuity arrangements... we can stop these which means they won’t be able to sell their produce here.”
The discussions over tit-for-tat measures began earlier this month after the European Commission announced that a ban on the export of live oysters, clams, scallops and mussels from Britain’s class B waters would become permanent because it is now listed as a third country.
It can now be disclosed that ministers have escalated contingency planning after Stella Kyriakides, the European Commissioner for Health and Food Safety, snubbed a request to meet the Environment Secretary George Eustice to try and resolve the row.
Mr Johnson is said to be personally angered by the move, which took ministers by surprise and which officials claim contradicted earlier assurances they had been given by the Commission.
On Saturday night, the Department for Environment, Food & Rural Affairs announced it would now widen the eligibility of the £23m support package it has announced for the fishing industry, in order to help fishermen and shellfish exporters affected by the ban.
The grants, which will begin in March, will cover three months of average fixed costs, and will be open to certain boats and shellfish exporters who have been hit by falling demand domestically during lockdown and disruption in exporting to the EU.
It is understood that officials are focussing on products which are already readily available in the UK, so as not to disadvantage British consumers.
It comes amid a series of other major flashpoints with the EU, including over vaccines, the post-Brexit arrangements for trade in Northern Ireland, and the status of the two sides’ respective ambassadors in London and Brussels.
This week Lord Frost, Mr Johnson’s chief Brexit negotiator, was appointed to the Cabinet and assumed many of Michael Gove’s responsibilities for managing future relations with Brussels.
Whitehall insiders have claimed his appointment is partly a signal of intent from the Prime Minister, who is said to want to take a “punchier” response to the EU and its “overly-bureaucratic” approach to the Northern Ireland protocol.
The protocol was set up to smooth trade friction created by the province remaining in the UK internal market while applying EU customs rules, but has been blamed for causing major disruption for traders moving goods between Britain and Northern Ireland.
On Firday, Lord Trimble, an architect of the Good Friday Agreement, joined calls from the DUP to scrap the protocol altogether, warning that it “willfully tears” up the “hard-fought” gains of the peace process.
Writing for the Irish Times, the former Ulster Unionist Party leader warned that the “unintended but unquestionably escalating tensions” created by it “represent a real and present danger to the lives of people living in Northern Ireland”.
Separately, The Telegraph can also disclose that Ben Habib, a former Brexit Party MEP, crossbench peer Baroness Hoey, and Jim Allister, the leader of the Traditional Unionist Voice party, are threatening a legal challenge against the Government to try and overturn it.
Arguing that the protocol flies in the face of the Act of Union 1800, the Good Friday Agreement, and that it effectively “partitions the UK”, they have instructed John Larkin QC, the former attorney general of Northern Ireland, to seek a judicial review, and have issued a letter before action to the Crown Solicitor’s Office.
Writing in The Telegraph on the fund for fisherman, Mr Eustice said: "The UK fishing industry produces some of the finest seafood in Europe from the waters around our coast.
"By supporting the sector through some of the current challenges we will ensure they are well placed to recover once the world turns the corner on this pandemic and emerges from lockdown."