The Government has warned the European Union it is considering action after the bloc imposed export controls on coronavirus vaccines and impinged on the post-Brexit deal on Northern Ireland.

Cabinet Office Minister Michael Gove spoke to the EU on Friday to express concern at its triggering of an aspect of the Northern Ireland Protocol to stop the unimpeded flow of jabs from the bloc into the region.

Downing Street warned the EU “as a friend and ally” not to disrupt the supply of vaccines, as the bloc took the surprise step while embroiled in a row with pharmaceutical giant AstraZeneca over shortfalls in the delivery of jabs.

Northern Ireland’s First Minister Arlene Foster described Brussels’ move as an “incredible act of hostility” that places a “hard border” between the region and the Republic of Ireland.

She demanded a “robust response” from the UK Government and spoke with Prime Minister Boris Johnson and Mr Gove as the EU provoked widespread condemnation from across the political spectrum by triggering Article 16 of the protocol.

Mr Gove, the Chancellor of the Duchy of Lancaster (CDL), spoke to his counterpart on the EU-UK Joint Committee, Maros Sefcovic, to “express the UK’s concern over a lack of notification from the EU about its actions in relation to the NI protocol”.

“CDL said the UK would now be carefully considering next steps,” a statement from Downing Street added.

No 10 added that it was “urgently seeking an explanation” from the EU and “assurances as to its intentions”, as the Government reiterated the need to preserve the commitments of the Good Friday Agreement.

“The UK has legally-binding agreements with vaccine suppliers and it would not expect the EU, as a friend and ally, to do anything to disrupt the fulfilment of these contracts,” a statement added.

The protocol, which is part of the Withdrawal Agreement, is designed to allow the free movement of goods from the EU into Northern Ireland, and prevent the need for a hard border on the island of Ireland.

But triggering Article 16 temporarily places export controls on the movement of vaccines, a move taken by the EU to prevent the region being used as a back door to move coronavirus vaccines from the bloc into the UK.

The European Commission’s new regulation states: “This is justified as a safeguard measure pursuant to Article 16 of that protocol in order to avert serious societal difficulties due to a lack of supply threatening to disturb the orderly implementation of the vaccination campaigns in the member states.”

It was not immediately clear what steps the Government was considering, but culture minister Caroline Dinenage did not rule out the UK invoking Article 16 in retaliation.

“The stakes are really high and everybody needs to keep their heads about them,” she said on BBC Radio 4’s Any Questions?, as she assured “we’re very confident in our supplies”.

Archbishop of Canterbury the Most Rev Justin Welby urged the EU to rethink its actions.

“Seeking to control the export of vaccines undercuts the EU’s basic ethics. They need to work together with others,” he tweeted.

Ireland’s Premier Micheal Martin expressed his concerns to European Commission president Ursula von der Leyen.

Mrs Foster said: “At the first opportunity, the EU has placed a hard border between Northern Ireland and the Republic of Ireland over the supply chain of the coronavirus vaccine.”

Shadow Northern Ireland secretary Louise Haigh said the EU’s move is “deeply destabilising” and urged the EU to “revoke this action”.

“Unilateral actions like this do nothing to aid the stability in Northern Ireland which the protocol was designed to preserve,” the Labour MP said.

Simon Hoare, chairman of the Commons Northern Ireland Affairs Committee, said it was “unconscionable folly” for the EU to escalate its vaccines row by triggering the protocol, adding: “We need calm, stability and level-headedness.”

Northern Ireland Secretary Brandon Lewis said the region receives its vaccines as part of UK procurement.

But preventing vaccines made with the EU from being exported could hinder the UK’s access to further supplies, particularly to the Belgian-made Pfizer jab.

Brussels has also demanded doses of the AstraZeneca vaccine manufactured in British plants in order to solve its supply shortage issues, as member states were forced to pause or delay their rollouts.

The EU’s “vaccine export transparency mechanism” will be used until the end of March to control vaccine shipments to nations outside the bloc.

It seeks to ensure that any exporting company based in the EU first submits its plans to national authorities.

European Commission executive vice-president Valdis Dombrovskis told a Brussels press conference: “Today the commission has adopted an implementing regulation making the export of certain products subject to an export authorisation.

“This regulation concerns the transparency and export of Covid-19 vaccines.”

The UK was not named among countries exempted from the new measures.

Meanwhile, AstraZeneca published a redacted version of its contract with the EU, which the bloc said was important for “accountability”.

The contract mentions that the firm would use “best reasonable efforts” to use European plants, including two in the UK, as production sites for vaccines destined for the EU.

The row intensified as the European Medicines Agency (EMA) authorised the AstraZeneca jab, which it developed with Oxford University, for all adults throughout the European Union.

German authorities had earlier said there was “not sufficient data to assess the vaccination effectiveness from 65 years” in only recommending its use on younger citizens.

But the EMA said that while there is not yet enough data from those aged over 55, protection is expected, and ruled that the jab can be used in older adults.

Oxford Vaccine Group director Professor Andrew Pollard said “there’s no reason to be concerned” about using the vaccine on older citizens.

“We’re quite confident because the immune responses are so similar that we will see immune responses in the same way as we have in younger adults,” he said.