Manufacturing activity in China slowed slightly in April from the previous month, official data showed on Wednesday, in a sign of further weakness in the world's second-biggest economy.

The purchasing managers' index (PMI) dropped to 50.6 in April, down from 50.9 the month before, according to the National Bureau of Statistics and the China Federation of Logistics and Purchasing (CFLP).

The PMI is a widely watched indicator of the health of the Chinese economy, with a reading above 50 indicating expansion while anything below that points to contraction.

The April figure marked the seventh consecutive month of expanding manufacturing activity in the country, but was down slightly from a nearly one-year high the month before.

"The April PMI index fell slightly, indicating that the foundation for economic stabilisation is still not solidified," analyst Zhang Liqun said in a CFLP statement.

"A slight slowdown in economic growth is possible," he said, adding that "effort should be made to stabilise domestic consumption, and increase the sustainability of the stabilisation of the economy".

British bank HSBC, whose survey focuses more on smaller enterprises, said last week that its preliminary PMI for April stood at 50.5, also down from a final reading of 51.6 in March.

The preliminary result came in lower on the back of decreasing new export orders and employment, according to the bank.

Its final reading for April will be announced on May 2.

China's economy expanded 7.8 percent in 2012, its slowest pace for 13 years, in the face of weakness at home and in key overseas markets.

Analysts had hoped the Chinese economy would rebound this year and drive growth globally after expansion of 7.9 percent in the last three months of 2012, snapping seven straight quarters of slowing expansion.

But the government in mid-April announced a surprisingly weak economic growth rate of 7.7 percent for the first quarter, below market expectations and fuelling fears the recent pick-up is faltering.

The International Monetary Fund last month lowered its forecast for China's growth this year to 8.0 percent, while Beijing in March kept its growth target for 2013 at 7.5 percent, unchanged from last year.