The American infectious disease expert Dr Anthony Fauci has said he does not agree with the UK’s approach of delaying the second dose of the Pfizer/BioNTech vaccine.

On Friday, Dr Fauci told CNN that the United States would not be following in the UK’s footsteps and would follow Pfizer and BioNTech’s guidance to administer the second dose of its vaccine three weeks after the first.

Despite an outcry from doctors, the UK’s chief medical officers defended their plans this week to delay the second dose of the Pfizer/BioNTech vaccine to patients, meaning people would now wait up to 12 weeks. The change is to prioritise giving more people their first dose.

Dr Fauci told CNN: “We know from the clinical trials that the optimal time is to give it on one day and for [the Moderna jab which is also approved in the US] wait 28 days and for Pfizer 21 days later.” He added that while you can “make the argument” for stretching out the doses, he would not be in favour of doing that.