BEIJING, Jan 15 (Reuters) - China's economy grew 4.0per cent in the fourth quarter from a year earlier, faster than expected but its weakest expansion in one-and-half years, National Bureau of Statistics data showed on Monday.

Gross domestic product (GDP) had been forecast to expand 3.6per cent from a year earlier, according to a Reuters poll of analysts, slowing from 4.9per cent in the third quarter.

GDP grew 8.1per cent in 2021, the data showed, faster than 8.0per cent expected by analysts.

On a quarter-on-quarter basis, GDP rose 1.6per cent in October-December, compared with expectations for a 1.1per cent rise and a revised 0.7per cent gain in the previous quarter.

China's economy got off to a strong start in 2021 as activity rebounded from a pandemic-induced slump the previous year, but it has lost steam due to a property downturn, debt curbs and strict COVID-19 curbs which have hit consumption.

Chinese leaders have pledged more support for the economy, which is facing multiple headwinds into 2022.

China's industrial output grew 4.3per cent in December from a year earlier, picking up from a 3.8per cent increase in November, official data showed.

The figure beat expectations of a 3.6per cent increase in a Reuters poll of analysts.

However, retail sales in December missed expectations with only a 1.7per cent increase from a year earlier, the slowest pace since August 2020. Analysts in the poll had expected them to grow 3.7per cent after rising 3.9per cent in November.

Fixed asset investment rose 4.9per cent in 2021, compared with the 4.8per cent increase tipped by a Reuters poll and 5.2per cent in the first 11 months of the year.