WHO said the global total deaths have climbed to 917,417 with more than 5,500 deaths in 24 hours.
According to the report, the biggest increases in infections were reported in India, the US and Brazil.
It says there have been more than 28 million confirmed cases worldwide and half of which have been in the Americas.
The previous one-day record for new cases was on September 6 when the WHO reported 306,857 new infections.
According to the WHO, India reported 94,372 new cases on Sunday, followed by the US with 45,523 and Brazil with 43,718.
More than 1,000 new deaths were recorded in the US and India while Brazil said 874 people had died from Covid-19 related illness in the past 24 hours.
India has the second largest number of confirmed cases in the world, behind the US. Last week, it reported nearly two million Covid-19 cases in August, the highest monthly tally in the world since the pandemic began.
The country saw an average of 64,000 cases per day- an 84 percent hike from average daily cases in July, according to official data.
The death toll has topped 1,000 every day since the beginning of September.
Brazil has recorded more than four million cases, the third highest in the world. It has the highest number of deaths in Latin America, with about 131,000 so far.
The US has recorded almost a quarter of the world's total number of coronavirus cases - more than six million. It saw an increase in the number of daily cases in July, but the numbers have fallen since then.
The US has the world's highest recorded death toll from Covid-19, with more than 194,000 fatalities.
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