AstraZeneca has warned EU countries to expect significant shortfalls to early deliveries of its coronavirus vaccine, in a fresh blow to the rollout of the bloc’s immunisation programme, European officials have said. The EU was expecting loom doses of the jab in the first quarter of the year. But people with knowledge of the discussions said the company may fail to deliver even half that amount, although they stressed that final figures had not been established.

AstraZeneca insisted there was no “scheduled delay” to the start of shipments of its vaccines, but said “initial volumes” would “be lower than originally anticipated due to reduced yields at a manufacturing site within our European supply chain”. “We will be supplying tens of millions of doses in February and March to the EU, as we continue to ramp up production volumes,” the company said, adding that the change in expected volumes did not affect the UK.

Details of the revised first-quarter deliveries to the EU were still being worked out but they could be less than 40m, several European officials said. Part of the reason for the uncertainty is that the provisional timetables are dependent on when the vaccine receives regulatory approval, which could happen next week. It was “not looking good in the short term” for AstraZeneca jab supplies, one European official said. A second described the proposed shortfall as “significant” while another branded it a “disgrace”.