The Cabinet will this week sign off on a dramatic plan to remove all of Ireland's oil reserves from the UK as the Government ramps ups its contingency plans for Brexit.
The move will see tankers filled with Irish oil transferred from British refineries and brought back to Ireland or to other EU member states.
Ireland stores almost 200,000 tonnes of oil in the UK but for national security reasons, this will now be removed ahead of Britain leaving the EU.
"We pay for storage there so that will have serious implications for UK refineries who have stored our oil for almost two decades," a senior Government source said.
Exporting Ireland's oil reserves from Britain is one of the most significant Brexit-related decisions which the Government has taken to date.
Tanaiste and Foreign Affairs Minister Simon Coveney will present detailed Brexit contingency plans to his Cabinet colleagues when they meet in Derrynane House in Co Kerry on Wednesday.
Mr Coveney will set out the need to hire hundreds of new customs and veterinarian staff to police airports and ports if an exit deal cannot be reached between the EU and the UK.
He will also highlight the need for major investment in customs infrastructure in the case of a 'no-deal' Brexit. The Cabinet is also expected to discuss the budget implications of Britain crashing out of the EU in March.
However, the main decision taken at the meeting will be on removing Ireland's oil reserves from the UK.
Under EU laws, every member state is obliged to have 90 days of oil reserves in case of national emergency.
For Ireland, this amounts to almost 1.5m tonnes of oil which includes petrol, diesel, gas oil, kerosene and jet engine fuel.
Around 1m tonnes of Ireland's oil reserves are held in ports around the country while the remaining 500,000 tonnes are kept in Britain, Holland, Denmark and Spain.
Once removed from the UK, the oil will be transferred either back to Ireland or to one of the EU countries which store Ireland's reserves.
It is also understood the Government has explored the possibility of France storing our oil. The Government could also remove the country's oil reserves from the UK through trade deals.
This would involve shifting ownership of oil reserves in other EU member states.
For example, ownership of British oil in France could be switched to Ireland and some of the Government's reserves could be left in the UK.
The Government has advanced its contingency planning after the EU Commission's Brexit prepardness unit issued instructions to member states to prepare for a 'no-deal' scenario.
"Drawing up contingency plans for the worst possible outcome is not a sign of mistrust in the negotiations," the document stated.
"The European Commission hopes for an agreement and devotes very significant resources and committed efforts to achieve this goal. Negotiations, on the other hand, can fail."
There are huge concerns in Government that Britain will come crashing out of the EU next March with no customs or trade deal.
The move would cause chaos in Irish ports and airports with huge delays expected for airline passengers and truck drivers.
A Department of Foreign Affairs spokesperson said the contingency plans focus on Ireland's east-west relationship with Britain and no proposals will brought to Cabinet relating to the border with Northern Ireland.
"There are no contingencies plans for a return of a border. We consider the UK's guarantee on that to be universal in all circumstances," the spokesperson said.
Writing in The Irish Times yesterday, Mr Coveney said: "The memo I will bring to Cabinet next week is about being ready for the change that is coming".
"We are particularly focused on the areas where the Government has direct responsibility and on measures that need to be taken on an east-west basis, such as customs and veterinary controls at ports and airports," he added.