BORIS Johnson has insisted the vaccination programme and route out of lockdown remain on track despite a shortfall in the expected supply of jags as he countered concerns over the Oxford/AstraZeneca vaccine, insisting it was “safe and effective”.

This was a direct quote from the EU regulator, which made clear the benefits of the AZ vaccine far outweighed the risks and it was not linked to an "overall risk" of blood clots. More than a dozen European countries - including Germany, Italy, Spain, the Netherlands, France and Sweden - halted the vaccine's rollout over clotting fears. Italy was the first say it would now resume use of the AZ jag.

The Prime Minister, 56, confirmed he would get his inoculation against Covid, using the Oxford vaccine, tomorrow.

A delay in deliveries from India and the need to retest a batch of 1.7 million doses is behind the issues with vaccine supply in April.

The problem with a shipment from the Serum Institute of India[SII] has been blamed by the body’s chief on the country’s government, although the Prime Minister made clear Narendra Modi’s administration has not stopped any exports.

“We have always said that in a vaccination programme of this pace and this scale, some interruptions in supply are inevitable,” Mr Johnson told a Downing St press conference.

“It is true that in the short term we are receiving fewer vaccines than we had planned for a week ago, that is because of a delay in a shipment from the Serum Institute – who are doing a Herculean job in producing vaccines in such large quantities – and because of a batch that we currently have in the UK that needs to be retested as part of our rigorous safety programme.

“As a result, we will receive slightly fewer vaccines in April than in March but that is still more than we received in February and the supply we do have will still enable us to hit the targets we have set,” he explained.

The over-50s and the clinically vulnerable will still be offered a first dose by April 15 and second doses will be available to around 12 million people in April.

Every adult will be offered a first dose by the end of July, as planned, he said.

The PM said: “Our progress along the road to freedom continues unchecked, we remain on track to reclaim the things we love, to see our families and friends again, to return to our local pubs, our gyms and sports facilities and, of course, our shops.”

Adar Poonawalla, Chief Executive of the SII, explained that the delay to a shipment of millions of doses was “solely dependent on India and it has nothing to do with the SII”.

“It is to do with the Indian government allowing more doses to the UK,” he said.

But Mr Johnson told the press conference: “The Indian Government has not stopped any export,” stressing how there was “very frequently” a delay in vaccine rollout programmes.

“It’s very important to stress whatever you may hear about the pressures that different countries are under to deliver vaccines for their public, these vaccines are a multinational effort, they are produced as the result of international co-operation and I want to stress that we in the UK will continue to view it in that spirit.

“We don’t have any bans on exporting stuff and we will continue to co-operate with our European friends,” he said.

The issues with supply came as regulators in the UK and Europe reaffirmed the safety of the Oxford/AstraZeneca jab.

The PM declared: “The Oxford jab is safe and the Pfizer jab is safe. The thing that isn’t safe is catching Covid, which is why it is so important that we all get our jabs as soon as our turn comes.”

He added: “So, let’s get the jab done.”