The UK and European Union are in talks to resolve a dispute over Covid-19 vaccine supplies as Boris Johnson warned that a trade war over jabs would result in “considerable” and “long-term” damage.

A joint statement said the two sides were seeking a “win-win” deal to increase supplies across the UK and EU

It came after the European Commission set out a tougher regime to stem supplies of jabs to nations faring better in the pandemic as the bloc’s states faced a third wave of cases.

Admitting it is a Covid-19 “hotspot”, the European Commission said on Wednesday it may not approve exports to nations with more advanced vaccine rollouts or where there is a better “epidemiological situation”.

The EU announced the move as it is embroiled in a row with AstraZeneca over supplies, but did not rule out Pfizer jabs being restricted to the UK if sufficient vaccines are not shipped to the bloc.

Member states were told to consider “reciprocity”, whether the destination country restricts its own vaccine exports, when authorising exports as the commission struck out against an alleged lack of British shipments.

Commission executive vice-president Valdis Dombrovskis denied the export authorisation mechanism was targeted at any one country but said 10 million jabs had moved from the EU to the UK since it introduced checks and that “zero doses” had returned from British plants.

But the Prime Minister told MPs: “I don’t think that blockades of either vaccines or of ingredients for vaccines are sensible, and I think that the long-term damage done by blockades can be very considerable.

“I would just gently point out to anybody considering a blockade or an interruption of supply chains that companies may look at such actions and draw conclusions about whether or not it is sensible to make future investments in countries where arbitrary blockades are imposed.”

The UK and the commission joint statement acknowledged the third wave of cases made co-operation more important – but no resolution had yet been reached.

“Given our interdependencies, we are working on specific steps we can take – in the short, medium and long term – to create a win-win situation and expand vaccine supply for all our citizens,” the statement said.

“In the end, openness and global co-operation of all countries will be key to finally overcome this pandemic and ensure better preparation for meeting future challenges.

“We will continue our discussions.”

It comes as it was revealed that India has placed a temporary hold on all exports of the AstraZeneca vaccine due to domestic demand caused by rising cases within the country.

Officials have described the move as a “temporary squeeze” which is expected to affect supplies until the end of April, according to the BBC, with some 190 countries under the Covax scheme likely to be affected.

Earlier, Mr Dombrovskis had argued the controls are necessary because while the EU is one of the “global hotspots of the pandemic” it is also the “largest exporter of vaccines”.

Member states and the commission will consider two key factors before authorising vaccine exports under the mechanism, which was extended until the end of June.

First they will consider whether the destination country restricts its own exports of vaccines, or raw materials, under plans to tackle “reciprocity”.

Second, under “proportionality”, they will consider whether the “conditions prevailing” in the destination country are “better or worse than the EU’s”.

Its epidemiological situation, its vaccination rate and its access to vaccines were listed as particular considerations.

Across the EU, just over 11% of adults have received a first dose of a Covid-19 vaccine but in the UK the figure is more than 54%.

Concerns over UK supplies will centre largely on Pfizer, the main vaccine export from the bloc and being produced in Germany and Belgium.

Mr Dombrovskis did not rule out restricting the Pfizer product, saying: “Concrete decisions will be taken on a case-by-case basis.”

A spokeswoman for Pfizer said it was assessing the “full implications” of the commission’s move, adding: “We have been clear and consistent with all stakeholders that the free movement of goods and supply across borders is absolutely critical to Pfizer and the patients we serve, particularly during this devastating global pandemic.

“Pfizer is deeply concerned by any legislation that threatens our ability to manufacture in, or export from, the European Union.”

Mr Dombrovskis maintained the EU’s criticism of British-Swedish pharmaceutical giant AstraZeneca, saying it had “only delivered a small portion of its agreed contractual commitments” to the bloc.

The commissioner said “continued shortfalls in production are not distributed fairly across different contracting countries”, in an apparent reference to the production of AstraZeneca jabs in the UK.

Denying the bloc was implementing an “export ban”, EU health commissioner Stella Kyriakides said: “We’re dealing with a pandemic and this is not seeking to punish any countries.”

Bernd Lange, chairman of the European Parliament’s international trade committee, hit out at Brussels’ stance.

“The EU Commission brings out the shotgun,” he said.

“But using the cluster munitions we may end up shooting ourselves in the foot because the supply chains for vaccine production might be affected and interrupted.”