The EU has lost a legal bid to force AstraZeneca to speed up delivery of Covid-19 vaccines or risk billions of euros in fines, the latest round in a bitter battle between the bloc and the UK-Swedish pharmaceutical company.

In a ruling on Friday, a court in Brussels criticised AstraZeneca for a “serious breach” of its contract with the EU after repeated shortfalls but refused to impose a new schedule demanded by Brussels that would have required the company to deliver 120m doses by the end of June or pay fines of €10 per dose per day.

The dispute between the European Commission and AstraZeneca has severely damaged the company’s standing on the continent and in February spiralled into a diplomatic row when Brussels threatened to exercise an emergency provision of the Brexit deal to stop vaccines entering the UK via Northern Ireland.

The Brussels court ruled that AstraZeneca should provide 80m doses by the end of September. However, in practice this should have no impact on AstraZeneca, which has already delivered 70m doses and plans to provide the remaining 10m before the end of this month.

The commission insisted that the court judgment would nonetheless put pressure on AstraZeneca because it had “laid the tracks for the delivery of future doses on the basis of clear contractual principles”, including supply from British manufacturing sites.

“The company will have to follow these tracks and it can no longer argue that it cannot use the UK plants for the production of vaccines for the European Union,” the commission said.

The ruling found that the pharma company’s failure to send the EU vaccines manufactured in the UK was inconsistent with making the “best reasonable efforts” on supply required by its contract. But it did not order AstraZeneca to use UK production to fulfil the EU order.

A UK plant operated by Oxford BioMedica is nonetheless expected to start manufacturing for the EU, according to a person familiar with the matter.

AstraZeneca was originally expected to supply up to 300m doses to the EU in the first six months of this year but that forecast was cut sharply after production problems.

With the pace of the EU’s vaccine rollout improving, using mainly Pfizer/BioNTech and Moderna jabs, and some countries imposing restrictions on the AstraZeneca vaccine after the discovery of rare blood clots, there is less practical need for the doses.

Jeffrey Pott, AstraZeneca’s general counsel, said: “AstraZeneca has fully complied with its agreement with the European Commission and we will continue to focus on the urgent task of supplying an effective vaccine, which we are delivering at no profit to help protect people in Europe and around the world from the deadliest pandemic in a generation.”

Ursula von der Leyen, president of the commission, said: “This decision confirms the position of the commission: AstraZeneca did not live up to the commitments it made in the contract. It is good to see that an independent judge confirms this.”

The court is due to hold hearings in September on a second case brought by the Commission seeking judgment on whether AstraZeneca failed in its duty to deliver on the supply contract.