Growth in China's manufacturing sector slowed in June after a better-than-expected performance in May, official data showed, as escalating trade tensions with the United States fuel concerns about a slowdown in the world's second-biggest economy.

China's economy has already felt the pinch from a multi-year crackdown on riskier lending that has driven up corporate borrowing costs, promoting the central bank to pump out more cash by cutting reserve requirements for lenders.

The official Purchasing Managers' Index (PMI) released on Saturday fell to 51.5 in June, below analysts' forecast of 51.6 and down from 51.9 in May, but it remained well above the 50-point mark that separates growth from contraction for a 23rd straight month.

The findings are in line with recent data including credit growth, investment and retail sales pointing to slowing growth in China's economy, as policymakers navigate debt risks and a heated trade row with the United States.

Significantly, the June new export orders index contracted for the first time since February, dropping to 49.8 from 51.2 in May.

A production sub-index fell to 53.6 in June from 54.1 in May, while a new orders sub-index declined to 53.2 from 53.8.

The PMI for large-sized firms fell to 52.9 in June from 53.1 in May, the index for medium-sized firms dipped to 49.9 from 51.0 while that for small firms rose to 49.8 from 49.6.