New Delhi, Dec 30 : The fast-spreading Omicron variant is likely to soon replace the Delta strain globally, experts in Singapore have warned, as countries after countries have reported a record surge in Covid cases. The warning comes as the World Health Organization (WHO) has cautioned that the more transmissible Omicron together with the currently circulating Delta variants might lead to "a tsunami of cases," putting immense pressure on national health systems. "From current data, it looks like Delta will go down over time relative to Omicron," Dr Sebastian Maurer-Stroh, executive director of the Agency for Science, Technology and Research Bioinformatics Institute in Singapore, told The Straits Times on Wednesday. Professor Dale Fisher, a senior consultant at the National University Hospital's Division of Infectious Diseases, said that Omicron is already dominant in Australia, India, Russia, South Africa and the UK. "We are seeing a global transition from Delta to Omicron because with a greater transmissibility, the virus is fitter and has a reproductive advantage," Fisher was quoted as saying. In India, the Omicron infection tally has climbed to 961, of which 320 patients have been discharged from hospitals. A Covid-19 tracker, developed by UK's University of Cambridge, has predicted that India may soon see an intense but short-lived virus wave "within days", even as the highly transmissible Omicron variant of Covid is spreading like wildfire in the country. Britain reported a new record increase of 183,037 coronavirus cases in the latest 24-hour period, bringing the total number of coronavirus cases in the country to 12,559,926, according to official figures. The total number of cases and deaths in the UK stands at 12,559,926 and 148,089 respectively, according to government data. The US, which has recorded more than 54 million cases to date, reported over 5,12,000 cases on Tuesday, the highest single-day spike since the beginning of the pandemic in 2020. According to data shared by the US Centres for Disease Control and Prevention (CDC), Omicron is estimated to be 58.6 per cent of Covid-19 variants circulating in the country. The Covid-19 infections with the Omicron variant in Germany increased by 2,686, or nearly 26 per cent within one day to a total of 13,129, according to the Robert Koch Institute (RKI) for infectious diseases. Canada reported 23,585 new Covid-19 cases, the first time to record more than 20,000 cases on a daily basis, elevating the cumulative total to 2,094,042 cases with 30,231 deaths, according to the state news agency. /IANS