LONDON: There is no evidence that blood clots are any more likely to occur after people are given AstraZeneca's COVID-19 vaccine, a spokesman for British Prime Minister Boris Johnson said on Tuesday, citing the country's medicine regulator.

"As the MHRA (Britain's Medicines and Healthcare Products Regulatory Agency) has said, blood clots occur naturally but there is no evidence that they are any more likely to occur following vaccination, so as such there's no evidence of any causal link between blood clots and the AZ vaccine," he told reporters.