A second coronavirus vaccine manufacturer has warned of supply issues, frustrating European Union efforts to distribute the jab.

UK drug-maker AstraZeneca said a production issue meant initial volumes would be lower than anticipated.

The European Commission said it was trying to obtain more information.

This comes on top of a halt to vaccinations in some parts of Europe due to a cut in deliveries of the Pfizer-BioNTech vaccine.

AstraZeneca, which developed its vaccine with Oxford University, disclosed the situation in a statement, but gave few details.

“Initial volumes will be lower than originally anticipated due to reduced yields at a manufacturing site within our European supply chain,” it said.

Reuters news agency quotes an unnamed EU official as saying that the company had told the EU that it would reduce to 31m – a cut of 60% – the number of doses it could deliver to the bloc in the first quarter of this year.

Unlike the Pfizer-BioNTech and Moderna vaccines, Astra-Zeneca’s product is yet to be approved by the EU’s drug regulator, though this is expected at the end of this month.

AstraZeneca has signed a deal with the EU to provide at least 300 million doses of its vaccine.