SHANGHAI (AFP) - China's manufacturing activity improved marginally in March from the previous month, the government said on Tuesday, but analysts said the world's second biggest economy remained weak.

The official purchasing managers index (PMI) was 50.3 in March, the National Bureau of Statistics said in a statement, up from 50.2 in February, which was an eight-month low.

The index tracks manufacturing activity in China's factories and workshops and is a closely watched indicator of the health of the economy. A reading above 50 indicates growth.

"The PMI index rose slightly in March and ended the trend of falling for three consecutive months.... It still indicates economic growth will stabilise in the future," the statement quoted Zhang Liqun, an economist at the state-backed Development Research Center, as saying.

The market had expected PMI to remain unchanged in March at 50.2, according to a poll of economists by Dow Jones Newswires.

A preliminary estimate by British bank HSBC, which gives greater weight to smaller companies, put China's PMI at a weaker 48.1 in March.

Analysts largely expect the government to take steps to boost the economy, though most have ruled out a huge stimulus package, instead expecting moves such as a cut in the amount of funds banks must place in reserve with the central bank.

"The rebound this time reflects the economy remained weak, but it's slightly better than market expectations," said Mr Zhou Hao, a Shanghai-based economist with ANZ bank.

"I expect the government to be more active... arranging fiscal expenditure in advance for some lagging projects," he told AFP.

Last month, Chinese Premier Li Keqiang set the nation's annual growth target at "around" 7.5 per cent, the same level as the goal for last year.

China's economy actually grew an annual 7.7 per cent in 2013, the same as in 2012 - which was the slowest since 1999.

The official Xinhua news agency on Monday quoted Chinese analysts as saying economic stimulus was unlikely.

"With further shrinkage in China's growth on the cards in Q1 (the first quarter), reform will be used to fend off economic slowdown rather than an economic stimulus," it said in an analysis.

China is due to release figures for first quarter gross domestic product on April 16.