China's gross domestic product expanded 7.8 percent year-on-year in July-September, data showed Friday, snapping two quarters of slowing growth in world's second-largest economy.

But analysts questioned whether the improvement in the country, a key driver of global growth, was sustainable.

The GDP result matched the median forecast in a survey of 11 analysts by AFP.

Growth for the first nine months of the year came in at 7.7 percent, the National Bureau of Statistics said.

"The overall national economy realised steady growth and enjoyed good momentum," the NBS said in a statement accompanying the figures.

"The major indicators stayed within the rational range, which was in favour of promoting economic restructuring and pushing forward reforms."

But its spokesman Sheng Laiyun warned of "pressures" in the form of a "complicated, volatile and severe" external environment, and accumulated structural problems in the economy.

Additionally, high comparative figures in the last three months of 2012 could mean China's growth rate does not accelerate in the fourth quarter, he added.

The latest result suggests China's economy remains on track to at least meet Beijing's own target for this year of 7.5 percent growth. The government usually announces a conservative number that it regularly surpasses.

Industrial production, which measures output at factories, workshops and mines, rose 10.2 percent in September year-on-year, the NBS said, while retail sales, a key indicator for consumer spending, was up 13.3 percent.

And fixed asset investment, a measure of government spending on infrastructure, rose 20.2 percent during the first nine months of the year.

The report card for the economy comes as China's new leadership has stressed the need to retool the country's growth model to one where private, consumer-led demand drives sustained -- albeit lower -- expansion.

Economists surveyed ahead of the release had said the jump was mainly a result of government stimulus since late June that featured increased rail and urban fixed-asset investment, tax cuts and looser monetary policy.

The pump-priming measures were taken after economic growth slowed for two straight quarters and following a 7.7-percent expansion for all of 2012 -- the worst performance since 1999.

But analysts are questioning whether such measures can be continued and some signs the recovery is waning have already emerged, highlighted by a surprising drop in exports last month.

"The GDP figure in the fourth quarter may be lower than the third quarter, as the momentum of the rebound is not that strong while the base from the fourth quarter last year is relatively high," Ma Xiaoping, a Beijing-based economist for British bank HSBC, told AFP.

Room for further monetary loosening is limited due to factors including rising inflation -- which hit a seven-month high of 3.1 percent in September -- and excess market liquidity, economists say, adding that at the same time skyrocketing local government debt and slowing fiscal revenue growth are restricting further tax incentives.

ANZ bank economists Liu Li-Gang and Zhou Hao credited what they called the "mini stimulus" package for the growth uptick.

The government will more than make good on its 7.5 percent growth target, they predicted, with "risk biased to the upside", but added that the rebound was "not on a solid footing".

There were few indications that inventories are being restocked, they said, a situation "reflecting a cautious mood" ahead of a key Communist Party meeting scheduled for November, when economic reforms could be announced.

But the gathering is unlikely to declare in detail how reforms would be carried out, said Yao Wei, Societe Generale economist in Hong Kong, adding a roadmap with some idea of time frame may be the most that can be expected.

"The real test of Beijing's reform resolution will be the action taken in the following three to six months," she wrote in a research note.

The economy expanded 2.2 percent in the third quarter from the previous three months, the NBS said, the strongest expansion by that measure in five quarters.

Sheng said: "Despite the growth rate volatility, the internal structure of the economy and the growth quality have improved.

"Looking forward, it is more likely that the Chinese economy will maintain steady and relatively fast growth."

Chinese shares closed up 0.24 percent.