Employees work at an auto manufacturing plant in Qingzhou, Shandong province. 

[Photo/WANG JILIN FOR CHINA DAILY]

China's manufacturing sector expanded at the highest rate last month since the COVID-19 outbreak, as the rebound in production quickened, a private survey said on Monday.

The Caixin China General Manufacturing Purchasing Managers' Index returned into the expansion territory in May and stood at 50.7, the highest level in the last four months, said a report released by media group Caixin on Monday.

The index came in at 49.4 in April. A PMI reading above 50 indicates expansion, while one below reflects contraction.

The pickup in operating conditions was backed by the acceleration in production amid further work resumption, the report said, with the output expansion rate climbing at the fastest level in more than nine years.

Supply chains also stabilized in May, following disruptions in prior months due to the restrictions to contain the epidemic, the survey showed.

Confidence of the surveyed manufacturers－around 500 private and State-owned manufacturers－brightened in May as the domestic economic order gradually normalized while some overseas economies started to partially resume work. The sub-gauge for future output expectations rebounded markedly to the same level as before the coronavirus outbreak, according to the report.

To sustain the recovery in the manufacturing sector, economists said there is a pressing need to expedite the rebound in domestic demand amid mounting external uncertainties, ranging from the pandemic situation to geopolitical and trade tensions.