Lawyers representing the European Union said on Wednesday that they would seek potentially billions of euros in penalties from AstraZeneca if the pharmaceutical company failed to deliver tens of millions of doses of its Covid-19 vaccine that it is contractually required to supply.

In the first hearing in a lawsuit that the bloc has brought against AstraZeneca, lawyers representing the European Union told the judges in a Brussels courtroom that the bloc was seeking to apply a penalty of €10 (about $12) per dose per day that it has been delayed.

The bloc is demanding 90 million doses from the company by the end of June. The proposed penalties, if accepted by the judge, would begin on July 1 and could quickly balloon into billions of euros.

The European Union paid a little over €2 per dose for the vaccine, which AstraZeneca sold at cost for the first stretch of the pandemic.

A European Commission spokesman on health issues said that the bloc was not demanding both the money and the doses, and that if the doses were delivered, the demand for the penalties would be dropped. The spokesman, Stefan De Keersmaecker, said that the lawsuit’s prime goal was to get AstraZeneca to deliver the doses.

The lawsuit, which has pitted the pharmaceutical company against one of its biggest clients globally, has inflicted reputational damage on both parties.

The company says that the delays were caused by production problems and do not constitute a breach of contract. But they have been blamed for the European Union’s slow vaccination start, as shortages meant that the inoculation rollout was delayed in many of its member countries.

The bloc has largely caught up in recent weeks and is on track to get at least one dose to 70 percent of its adult population by July. But the political and reputational impact of the sluggish start has been damaging.