China's fixed-asset investment, a main measure of government spending on infrastructure projects, rose by its slowest rate in more than 12 years in the months from January to April, the government said today.

Fixed-asset investment rose by 17.3% year-on-year in the first four months of the 2014, slowing from 17.6% in the first quarter, the National Bureau of Statistics (NBS) said.

The figure is only released cumulatively, and the reading was the lowest since the increase for the whole of 2001, when it stood at 13.7%, NBS data showed.

Growth in the world's second-largest economy is decelerating, but leaders in Beijing say they want to wean the country off investment as the key driver of expansion and shift the focus to consumer spending.

Meanwhile, China's industrial output increased by 8.7% year-on-year in April, the NBS also said, edging down from 8.8% a month earlier. 

Retail sales, a gauge of consumer spending, increased by 11.9% last month from a year ago, the NBS added, down from an increase of 12.2% in March.

Today's figures are likely to add to concerns over the weakening of China's economic growth, a key driver of the global recovery.

The country's gross domestic product grew 7.4% in the first three months of 2014, weaker than the 7.7% in October-December last year and the worst since a similar 7.4% expansion in the third quarter of 2012. 

Premier Li Keqiang in March announced a growth target of "around 7.5%" for 2014. 

Top officials have publicly ruled out a massive stimulus package to kick-start growth and have instead introduced a series of smaller measures, including a cut in the amount of money rural lenders have to keep in reserve, tax breaks for small enterprises and targeted infrastructure outlays.