Asian currencies weakened on Friday, with the South Korean won leading the pack, as the rising death toll and economic damage from the coronavirus epidemic cast a shadow on global economic outlook. The toll in mainland China jumped to 636 by the end of Thursday, up by 73 from the previous day, with the number of infections at 31,161.

The yuan slipped as much as 0.2% to 6.983 per dollar, and was poised for its second weekly decline. The Chinese central bank warned that the domestic economy could be disrupted in the first quarter due to the outbreak, adding that a recovery could be expected once the virus is brought under control.

"Relief gains this week are now showing signs of slowing as reality check plays catch-up," Maybank analysts said in a note. "Renewed fears of local transmission or rise in spread outside China will dampen sentiment and unwind earlier gains."

Upbeat US economic data, China's stimulus measures and positive headlines regarding the Sino-US trade war gave traders some respite this week amid worries over the virus. The won eased as much as 0.8% to 1,188.70 per dollar, marking its biggest intraday drop in more than a week, and was on track to snap two weeks of declines.

South Korea's vice finance minister said the virus could have a negative impact on the country's domestic consumption, exports and auto industry, adding that market stabilisation measures would be taken if volatility rises. The Singapore dollar fell marginally, and was poised for a 1.8% weekly drop, its biggest since November 2016.

DBS, Singapore's biggest bank, downgraded the city-state's 2020 growth rate to 0.9% from 1.4%, due to an expected economic impact from the coronavirus. The Indonesian rupiah declined 0.4%, while the Thai baht and the Malaysian ringgit softened 0.3% each.

Meanwhile, the Philippine peso was little changed, a day after the central bank cut interest rates and said it was prepared for further easing to shield the economy from the coronavirus impact. Earlier on Thursday, India's central bank kept rates on hold but worries about the economic impact of the virus outbreak has raised the chances of further monetary policy easing across Asia this year.