AstraZeneca's Covid vaccine shot is safe and there is no evidence of health risks, the UK's health minister wrote in a newspaper article published on Wednesday, after some EU countries halted rollouts over fears of blood clots.
Matt Hancock urged the British public to take the vaccine even after countries including France, Spain and Germany suspended it.
The European Medicines Agency, which previously approved the jab, is conducting a review of the vaccine but said in the meantime it remained convinced of its benefits.
"There is no evidence that vaccines caused these clots," Hancock wrote in The Sun, stressing that the jab had the backing of the EMA, the World Health Organization and Britain's medicine's regulator.
"More than 11 million doses of the AstraZeneca vaccine have now been administered across the UK," he wrote.
"The rate of reported cases (of clots) among the people vaccinated is lower than what would be expected to happen naturally in the general population."
Britain has given nearly 25 million people a first dose of a Covid vaccine, after starting a mass inoculation programme in December last year.
The AstraZeneca jab, developed with scientists at the University of Oxford, is central to getting the country out of lockdown restrictions and back to normality.
London has ordered 100 million doses of the low-cost shot, which has been hailed as a potential gamechanger in the global fightback against the virus.
France and Italy have said they will "promptly restart" giving the jab if the EMA review allows it.
As Britain has surged ahead with its vaccination programme, European countries have been accused of playing politics to distract from their sluggish inoculation rollouts.
AstraZeneca announced in January it could only deliver a third of the 120 million doses initially promised to the 27 EU member states in the first quarter, sparking criticism.
As Europe looks to speed up its immunisation programme, Hancock wrote that this week the UK will get "a boost in supply" that will help accelerate the rollout.
Every adult is now expected to get a first dose of a vaccine by the end of July, he added.