The European Union has exercised an option to acquire an additional 100 million doses of BioNTech and Pfizer's Covid-19 vaccine, the companies said on Monday.
This brings the total number of doses to be delivered to the 27 EU members to 600 million in 2021, the companies said in a statement.
The option to buy an extra 100 million doses was part of a purchase agreement the EU signed with Pfizer and BioNTech in February.
Pfizer and BioNTech last week agreed to accelerate Covid vaccine deliveries to the EU by 25 per cent this quarter, bringing forward shipment of 50 million doses that had originally been scheduled for the fourth quarter.
The EU needs more shots from the US-German alliance to offset challenges in the rollout of vaccines from AstraZeneca and Johnson and Johnson.
Johnson and Johnson put its shipments on hold while regulators review rare cases of blood clots in a few people who got its shot.
Meanwhile, a number of EU countries have restricted use of the AstraZeneca shot due to a link with similar, but still very uncommon, cases of blood clotting combined with low blood platelets.
More people were diagnosed with Covid-19 worldwide during the past seven days than any other week since the start of the pandemic - topping 5.2 million globally.
The trend, just days after the world surpassed 3 million deaths, comes as countries are rolling out vaccinations in an effort to get the virus under control.
The data from Johns Hopkins University showing a 12 per cent increase in infections from a week earlier casts doubt on the hope that the end of the pandemic is in sight. The weekly increase surpassed the previous high set in mid-December.