London, May 28 : UK Health Secretary Matt Hancock has said that that almost half, and possibly three-quarters, of all new coronavirus cases in the country are of the B.1.617 variant. Addresing a press conference at Downing Street on Thursday, Hancock said: "We always expected cases to rise as we rolled out the roadmap, we must remain vigilant." Noting that another 3,542 people in have tested positive for Covid-19 in the past 24 hours, the highest since mid-April, Hancock said the government is "unwavering in our focus to protect life from this daily virus", reports Xinhua news agency. On a more positive note, Hancock said the vaccine "is severing the link between cases and hospitalisations", urging the public to take the jabs when offered so that cases alone no longer require stringent restrictions. The increase in cases remains focused in hotspots where surge testing and vaccines rollout are taking place, he added. According to Hancock, three in four adults now have antibodies with vaccinations estimated to have prevented 200 deaths and 600 hospitalisations last week. Jenny Harries, Chief Executive of the UK Health Security Agency, said there has been a "sustained and sharp decline" in cases from the middle of January but more recent data showed a "suggestion" of an upward rise. Asked why lockdowns are being eased amid increasing concerns over the B.1.617 variant, Hancock said the situations are being monitored, but that vaccines look to be effective against it. Earlier Thursday, Prime Minister Boris Johnson said there's nothing "in the data" to suggest final step of roadmap exiting the lockdown can't go ahead on June 21. "As I have said many times I don't see anything currently in the data to suggest that we have to deviate from the road map, but we may need to wait," he said during a visit to a hospital. More than 38.6 million people in Britain have been given the first jab of the coronavirus vaccine, according to the latest official figures. The UK has so far reported 4,473,677 coronavirus case since the onset of the pandemic last year, while the death toll has surged to 127,758. /IANS