The European Union has bought up to 300 million extra Covid-19 vaccine doses from US firm Moderna, European Commission chief Ursula von der Leyen said.

The new deal, which she hailed as “good news”, adds to the EU's vaccine stock as it strives to meet a target of fully vaccinating 70 per cent of adults by mid-September.

The commission now has access to a vaccine “portfolio” of 2.6 billion doses of three EU-authorised vaccines and three more prospective ones, to be provided this year and next, von der Leyen told a media conference, according to AFP.