Labour leader Sir Keir Starmer has called for the Government to spell out exactly what the problems with vaccine supplies are.
Sir Keir also insisted people should feel confident in taking the Oxford-AstraZeneca vaccine after its use was controversially suspended by some European countries.
In the Commons on Thursday afternoon, Health Secretary Matt Hancock said the delay in deliveries from India and a need to retest a batch of 1.7 million doses is behind an expected shortfall in coronavirus vaccine supply.
But Sir Keir, speaking after a visit to a vaccination centre in Edinburgh alongside the Scottish Labour leader, Anas Sarwar, said the UK Government needs to be clearer about the issues it faces with vaccine supply.
“The vaccine rollout has been going really, really well and that’s a good thing,” he said.
“So, I am concerned about the delays, we need to get to the bottom of it and we need transparency from the Government about what the problem is.
“I say that in a constructive spirit because we want everybody to be vaccinated as soon as possible.”
After a dozen European countries suspended use of the Oxford-AstraZeneca vaccine over isolated cases of blood clotting, which vaccine regulators and health experts said no causal link has been made with the jab, Sir Keir said people should not worry about being vaccinated with it.
He told the BBC: “I think the AstraZeneca vaccine is safe, the experts are telling us it is safe and I would urge everybody who is invited to come forward to have the vaccine.
“I myself had AstraZeneca last Sunday, so I’m not just saying this – I’ve had that vaccine, the Oxford-AstraZeneca, it’s safe.
“Please, if you are invited to come forward, come forward and have the vaccine.”
In an interview with Sky News, Sir Keir criticised the Prime Minister for previously dismissing female MPs’ claims of sexist abuse as “humbug” and said: “I think that he was far too dismissive of misogyny”.
However, he welcomed Boris Johnson’s “constructive tone” when challenged about how to tackle violence against women at PMQs on Wednesday.
“I think he’s got some way to go on this but look, yesterday was constructive,” Sir Keir said,
“But if we are to do something about violence against women and girls, we need everybody to pull together.”
Ahead of his visit to Scotland, his first since Mr Sarwar was elected, Sir Keir said: “First and foremost, today is about paying tribute to the NHS staff across Scotland who have been on the front line of this pandemic.
“They have battled Covid heroically, and now they are helping defeat it by rolling out the vaccine.
“Once this virus is beaten, Scotland’s recovery must be the number one priority for its Government. That’s what Anas Sarwar and Scottish Labour are offering in May’s election.
“Scottish Labour, under Anas’s leadership, is the only party serious about tackling the injustices which have been brutally exposed by Covid.
“Whether it’s education, the economy, or Scotland’s NHS, a vote for Scottish Labour in May is a vote to secure Scotland’s recovery.”