A rise in coronavirus cases of 50% has been blamed on increased numbers visiting pubs and restaurants ahead of the second lockdown coming into force.

More than 33,000 cases were recorded in the UK on Thursday, the highest figure on record and a jump of more than 10,000 in one day.

Scientists said the spike was likely to reflect increased socialising before lockdown, though this appeared to be based on assumptions rather than a direct link.

Professor Carl Heneghan, director of the Centre of Evidence-Based Medicine at Oxford University, said: “These figures are going through the roof, and it’s not really surprising when we saw scenes like Christmas Eve last week before we went into lockdown.

“The problem is when these policies are drawn up the Government assumes everyone will behave the same way, and they just don’t take account of the fact that many people saw it as a last chance to get out. We had some quite crazy scenes last week, with pubs and restaurants full and some of them even more crowded because others were already closed.”

Health officials warned against reading too much into any one day’s data but raised fears that the trend could continue in coming days because there is typically a five-day lag between infection and symptoms showing, and some days more to secure a test and get results.

Paul Hunter, professor of medicine at the University of East Anglia, said that while one day’s data was hard to judge, socialising ahead of lockdown may have contributed to the spike.

He said: “If cases remain this high for another day or so then it will pretty much be down to people having more social contacts – partying before lockdown.”

Experts said longer-term figures also suggest a rise in cases towards the end of October as people “rushed to the pub” amid mounting speculation that another lockdown would be announced.

New data from Imperial College’s React surveillance study, which has been monitoring the pandemic since May, found cases started to decline last month but jumped unexpectedly around the time when rumours about harsher restrictions were rife.

Steven Riley, professor of infectious disease dynamics at Imperial, said people going to the pub before lockdown ” could be, partly” to blame for the rise in cases.

“Clearly, we’ve thought a lot about this a lot. There was a lot happening over that period. There was half-term in many areas, it was a wet month and there were cold periods, and there was a lot of talk about lockdown. Something happened in people’s behaviour that caused things to go down and then go back up again, and it appears to be consistent across the country.”