Asia's factory activity weakened in August as manufacturers felt the pinch from rising input costs and slowing global demand, but an unexpected rebound in China offered some hope for the region's export-reliant economies, private surveys showed.

Three of China's biggest banks on Friday cut interest rates on a range of deposits in an effort to ease pressure on their shrinking margins as lenders move to lower mortgage rates to prop up a struggling property sector and a faltering economy.

Oil prices steadied at three-week highs in Asian trade on Friday as the prospect of tighter supplies, stemming from deeper Saudi and Russian production cuts, largely offset concerns over slowing economic growth. 

Chinese factory activity unexpectedly grew in August, a private survey showed on Friday, as manufacturers benefited from an uptick in new orders on improving local demand.

Vietnam's exports in August fell 7.6% from a year earlier, official data showed on Tuesday, making a sixth straight month of decline as weak global demand weighs on the export-reliant economy.

South Korea's exports likely fell in August for an 11th consecutive month, a Reuters survey showed on Wednesday, as economic recovery in top export market China continues to stutter.