China's manufacturing sector regained expansion in January after three consecutive monthly shrinkages, with major sub-indices posing surges.

The purchasing managers' index (PMI) for China's manufacturing sector came in at 50.1 in January, up from 47 last December, data from the National Bureau of Statistics (NBS) showed Tuesday.

A reading above 50 indicates expansion, while a reading below reflects contraction.

Of 21 surveyed industries, 18 reported rising PMIs month on month, as the country's epidemic response has entered a new phase and production has gradually recovered, the bureau's senior statistician Zhao Qinghe said.

The sub-index for large enterprises stood at 52.3 in January, up 4 percentage points from the previous month, and those for small and medium-sized enterprises also rose by different extents, the data showed.

"The labor shortage in enterprises has been eased to ensure production," Zhao said.

The sub-index for new orders gained 7 percentage points to 50.9, while that for production stood at 49.8, up 5.2 percentage points from last December.

"Both demand and production saw remarkable recoveries," Zhao said.

The PMIs of hi-tech manufacturing, equipment manufacturing, and consumer products industry all rebounded to above 50, while the warming sub-indices for the expectation of production and management reflected strengthened business confidence, he noted.

The NBS the same day said the PMI for China's non-manufacturing sector came in at 54.4 in January, up from 41.6 last December.

Ending a six-month losing streak and back to positive territory, the figure was the second highest in the past 12 months, only slightly lower than the reading of 54.7 last June.

The sub-indexes for the services and construction sectors in January stood at 54 and 56.4, respectively.

Of all 21 surveyed industries, 15 saw business expansion, Zhao said, adding that retail, hotel, and catering sectors, previously hardest hit by COVID-19, resumed expansion.

He believes consumer sentiment has improved significantly and market activity has picked up.

Also on Tuesday, the International Monetary Fund (IMF) projected China's economy will grow by 5.2 percent in 2023, 0.8 percentage points higher than October 2022 forecast.

The IMF said in the newly released update to its World Economic Outlook report that the recent reopening has paved the way for a faster-than-expected recovery of China's economy.