The government reported 967 new Covid-19 cases on Sunday, the most ever recorded in a 24-hour period, for an accumulated total of 32,625 since the pandemic began. No new deaths were reported, leaving the toll at 97.

The Centre for Covid-19 Situation Administration (CCSA) said all but three of the cases – imports from Malaysia, the United Arab Emirates and France – were locally transmitted: 530 recorded at hospitals and 434 revealed from mass testing in communities.

Bangkok led new infections in both categories at 236, followed by Chiang Mai (189), Chon Buri (180) and Samut Prakan (48).

Sophon Iamsirithaworn, the deputy director-general of the Disease Control Department, said most new transmissions were related to the pub clusters that then spilled to other provinces across Thailand.

"The situation in our country is worrying," Dr Sophon said.

Infections have been linked to 140 pubs in 15 provinces. Bangkok topped the list with 85 nightspots, led by Krystal Club in Thong Lor where 211 infections have been detected since the beginning of this month. Chon Buri had 11, Prachuap Khiri Khan registered nine, Pathum Thani seven and Chiang Mai six, according to CCSA data.

The official also urged people living along the Thai-Cambodian border to beware the Covid spread in the neighbouring country, where 477 new cases and two deaths were logged yesterday, according to the Worldometers website.