European regulators have said each vaccine vial contains six doses, following a request from the companies making the jab. The change comes with immediate effect.

Germany's Health Ministry on Friday said European Union regulators had approved doctors drawing up to six doses from each vial of the BioNTech-Pfizer coronavirus vaccine.

Ministry spokesman Hanno Kautz told reporters the change would come into effect immediately, boosting the number of available doses by 20%.

The European Medicines Agency (EMA) said last month that it had received a request from the companies to allow more than the permitted five doses per vial to be drawn.

How does the change work?

The agency on Friday said its human medicines committee has recommended updating the product information to clarify that each vial contains 6 doses.

Using specific syringes, an extra shot on the vaccine — known as Comirnaty — can be safely eked out, the EMA explained in a written statement.

Across the EU, many doctors have already been drawing six doses from each vial, The practice is already officially permitted in the US, Britain and elsewhere.

Pharmaceutical firms regularly put more vaccine into vials than necessary, so minimum dosage can be ensured even if there is spillage.

How many vaccine doses does the EU have?

The news came after the EU on Friday announced that the bloc had bought up to 300 million additional BioNTech-Pfizer vaccine doses on top of 300 million already ordered.

EU member state governments and the European Commission itself have come under heavy criticism amid frustration over the relatively slow start of the inoculation campaign for the 450 million people who live in the EU.

The Commission has denied accusations that it did not order enough doses, pointing instead to bottlenecks in production and delivery.