Mainland stocks tumbled on Friday and posted their biggest weekly decline since late December, joining a global market selloff with tech shares leading declines.

The Hang Seng Index ended trading for the week 615 points, or 2.38 percent, down at 25,220, which is a five-week low.

The benchmark is down five percent for the week, the biggest loss since April 7.

The Hang Seng tech index declined 3.2 percent, the sixth straight losing session to its lowest since August.

Mainland indices were hit a tad harder, with the benchmark Shanghai Composite Index down 2.45 percent at 3,834 in the biggest single-day decline since April 7.

That brought the week's loss to 3.9 percent, the worst since December 30, 2024.

The Shenzhen Component Index dropped 3.41 percent to 12,538 and the ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, lost 4.02 percent to 2,920.

The blue-chip CSI 300 Index declined 2.4 percent in the biggest single-day decline since April 7.

That brought the week's loss to 3.9 percent, the worst since December 30, 2024.

The combined turnover of the Shanghai and Shenzhen indexes reached nearly 1.97 trillion yuan, up from 1.71 trillion yuan on Thursday.

Shares related to shipbuilding posted gains while those related to lithium mines and non-ferrous metals suffered major losses.

The Shanghai Composite Index dipped 2.5 percent at market close, the biggest single-day decline since April 7.

That brought the week's loss to 3.9 percent, the worst since December 30, 2024.

The blue-chip CSI 300 Index declined 2.4 percent and posted a weekly loss of 3.8 percent, also the worst in nearly a year.

Declines were broad-based, with tech shares leading the slide following their US counterparts' weak session on Wall Street overnight.

The CSI AI Index lost 4.2 percent and the CSI Semiconductor Index declined 4.3 percent.

Defensive plays also posted losses, with the banking sector slipping one percent, liquor down 1.1 percent and consumer staples declining 0.8 percent.

"The move looks more like risk-off sentiment in recent overheated outperforming sectors," analysts at Goldman Sachs said, adding that some money might start to seek shelter in some of this year's underperforming sectors.

"Market sentiment weakened toward year-end on lower risk appetite and recent muted economic data," analysts at Morgan Stanley said.

Index upside is modest with moderate earnings growth and valuation settling at a higher regime, they added.

The next policy window to watch for markets will be after the Central Economic Work Conference in mid-December, analysts at Citi said.

However, despite the weakness in China shares, UBS said investors don't appear to worry too much that the US selloff may not impact flows into Asia and China markets immediately.

"If the liquidity-driven US selloff persists long enough to deflate the AI bubble healthily, it could benefit emerging markets, particularly China." (Reuters/Xinhua)