Chinese manufacturers' operating conditions deteriorated for the first time in 11 months, purchasing managers' data from Caixin and IHS Markit showed June 1.

The Caixin China General Manufacturing Purchasing Managers' Index, or PMI, fell to 49.6 in May, down from 50.3 the month before and below the neutral 50.0 point separating improvement from deterioration.

Total new orders during May increased at the slowest pace since July 2016. Customer demand was also relatively subdued both at home and overseas, with new export sales rising at a marginal pace, the report said.

"China's manufacturing sector has come under greater pressure in May and the economy is clearly on a downward trajectory," said Zhengsheng Zhong, director of macroeconomic analysis at CEBM Group.

On May 31, the Chinese National Bureau of Statistics had reported manufacturing PMI at 51.2 for the second consecutive month in May.