The United Kingdom will have “no choice” but to block deliveries coronavirus vaccine raw materials to the European Union if the bloc follows through with its threats to ban the export of vaccines promised to Britain, a senior government official told a British newspaper.

Over the weekend, embattled EU Commission president Ursula von der Leyen threatened to block the export of up to 19 million doses of the Oxford-AstraZeneca vaccine to Britain, as well as possibly barring exports to the United States, amid widespread failure to vaccinate populations across the 27 EU member-states.

In response to the threats, a senior government official told The Sun on Monday that the British government would have “no choice” but to reciprocate by blocking the export of ingredients required to manufacture the jab to the EU.

The source said that “politically and morally it’s a no brainer,” going on to say that “the British public would not put up” with anything less.

Defence Secretary Ben Wallace told the BBC that: “The grown-up thing would be for the European Commission and some of the European leaders to not indulge in rhetoric.”

Wallace also said that “If contracts get broken and undertakings, that is a very damaging thing to happen for a trading bloc that prides itself on the rule of law, prides itself on following contracts … and I think the Commission knows deep down that the world is watching what happens. And also it is counterproductive because the one thing we know about vaccine production and manufacture is that it is collaborative.”

On Monday it was revealed that Prime Minister Boris Johnson called European Union leaders, including French president Emmanuel Macron and Germany’s Chancellor Angela Merkel, in a push to convince the EU to keep trade of the vaccine open.

Speaking to reporters, Mr Johnson warned that Britain will see the third wave of the coronavirus “wash up on our shores” from Europe. He said that Britons should be “under no illusion” that the United Kingdom will “feel the effects” of the rising caseload across the Channel.

EU leaders are expected to meet for a summit on the matter of vaccine exports on Thursday.

On Sunday, the European Commissioner for Financial Stability, Mairead McGuinness, said that all options are currently on the table.

“Both the EU and the UK have contracts with AstraZeneca and my understanding is the company is supplying the UK but not the European Union,” she told the BBC, adding: “We are supplying the UK with other vaccines, so I think this is just about openness and transparency.”

So far, European countries such as France, Germany, and Italy have only vaccinated around 12 per cent of their populations. All three countries are currently imposing harsher lockdown restrictions on their people, yet again.

Taken as a whole, only around ten per cent of people within the EU have received a single dose of the vaccine, compared to over 50 per cent in the United Kingdom.

Brussels has blamed the shortfall in inoculations on British-Swedish pharmaceutical giant AstraZeneca, claiming that the company has only delivered 30 per cent of the promised vaccines.

However, the delay in securing vaccines for Europe was significantly impacted by bureaucratic logjams which saw the EU sign contracts with AstraZeneca three months after Brexit Britain.

Follow Kurt Zindulka on Twitter here @KurtZindulka