LONDON: British Prime Minister Boris Johnson said Wednesday that Covid-19 vaccines are proving effective against a variant that has spread like wildfire in India and denied the government was being lax on travel from hotspots.

Johnson has been under pressure for delaying restrictions on travel to and from India last month, at a time when he was still planning to head to a trade-focused summit in New Delhi.

The trip was eventually called off as India succumbed to a devastating new wave of infections, and it was then quickly added to the UK’s “red list”, meaning arrivals have to quarantine in hotels at their own cost.

But more than 100 flights have landed from India since then and the variant has been spreading in Britain, especially in areas with large South Asian communities, potentially endangering plans to reopen the economy fully from June 21.

“We have increasing confidence that vaccinations are effective against all variants including the Indian variant,” Johnson said in parliament. “We have one of the strongest border regimes anywhere in the world,” he added, after a day of confusion from ministers on Tuesday about whether travel is allowed to “amber” countries including most of Europe.

Travel to amber countries should only be undertaken for “any emergency or extreme reason” such as family illness, the prime minister said.

Health Secretary Matt Hancock meanwhile is facing calls to explain his claim that the rise of the Indian variant in Britain is due to a refusal by some people to get vaccinated.

Official data has shown the variant actually took hold due to travellers coming from India, raising more questions about the government’s delay in adding the country to the red list when Pakistan and Bangladesh were already on it.

The data shows that positive tests among travellers coming from India were higher than those from Bangladesh and comparable to Pakistan, well before the new restrictions took effect for India on April 23.

Hancock told parliament on Wednesday that 2,967 cases of the B1617.2 variant have now been identified in Britain, up nearly one-third since Monday.

Announcing “surge testing” in several more areas, he said “the race between the virus and the vaccine has got a whole lot closer”.