SEOUL (REUTERS) - Thousands of trainee doctors in South Korea returned to work on Tuesday (Sept 8) after ending a more than two-week strike as the country grappled with sustained three-digit rises in new daily coronavirus infections.

The Korea Centre for Disease Control and Prevention (KCDC) reported 136 new cases as of midnight on Monday, after the rate fell to a three-week low of 119 a day earlier. The total infections rose to 21,432, with 341 deaths.

The daily tally has steadily dropped since it reached a peak of 441 last month after the government imposed unprecedented social distancing rules to blunt a second wave of outbreaks from churches and political rallies.

Efforts to curb the latest epidemic has been complicated by the strike launched on Aug 21 by some 16,000 intern and resident doctors against the government's medical reform proposals.

The trainee doctors restarted work after agreeing to end the walkout on Monday, though many medical students continued to resist final licensing exams as part of the protest.

The intern and resident doctors are the backbone of healthcare services in emergency rooms and intensive care units, and hospitals increasingly grappled with delays and disruptions amid constant rises in Covid-19 patients.

The authorities are weighing whether to extend the social distancing curbs ahead of Chuseok, one of the country's biggest holidays this month, which would see tens of millions of people travel nationwide.

President Moon Jae-in said the daily numbers are expected to drop below 100 by the holiday, though health officials have urged against visits and gatherings.

The curbs, including limiting the operation of on-site dining after 9pm local time in the Seoul metropolitan area, were extended for another week until Sept 13.

Seoul city on Tuesday imposed an entry ban on some of the biggest parks along the Han River which saw a surge in the number of nightly visitors since the restrictions took effect.

Cafes, convenience stores and carparks in all 11 riverside parks will be closed after 9pm.

"If you don't keep distance without wearing a mask properly for a long time, the risk of infection goes quite higher even though you're outside," KCDC deputy director Kwon Jun-wook told a briefing.