New coronavirus infections in South Korea exceeded 4,000 in a day for the first time since the start of the pandemic as a delta-driven spread continues to rattle the country after it eased social distancing in recent weeks to improve its economy.

The Korea Disease Control and Prevention Agency said most of the new 4,116 cases reported Wednesday came from the capital Seoul and its surrounding metropolitan region, where an increase in hospitalisation has created fears about possible shortages in intensive care units. The country's death toll is now 3,363 after 35 virus patients died in the past 24 hours.