BRUSSELS, Jan 4 (Reuters) - 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 whether there is a way to add additional doses to those for which we already have a deal," the spokesman said. (Reporting by Francesco Guarascio @fraguarascio; Editing by Kirsten Donovan)