BRUSSELS: The European Commission is in discussions with Pfizer and BioNTech about the possibility of ordering more doses of their COVID-19 vaccine, in addition to the 300 million shots already covered under an existing contract, a spokesman said on Monday.

"The Commission is checking with the companies whether there is a way to add additional doses to those for which we already have a deal," the spokesman told a news conference.

The spokesman declined to answer a question on whether a German deal for more doses of the same vaccine could clash with possible new orders by the European Union.

The EU is distributing jointly procured vaccines on a pro-rata basis to the 27 member states based on their populations.

The bloc has already ordered 200 million doses of the Pfizer-BioNTech vaccine and has taken up an option to buy another 100 million under a contract signed with the two companies in November.

The Pfizer-BioNTech vaccine is the only one to be authorised in the EU so far. The EU drugs agency will decide on the approval of the vaccine developed by biotech firm Moderna on January 6.