SAN FRANCISCO -- Social media service Reddit Inc. says it has raised US$300 million in a financing round led by Chinese internet giant Tencent.

Reddit's CEO, Steve Huffman, told CNBC on Monday that values the privately held company at US$3 billion.

Half the new money came from Tencent, Asia's most valuable tech company. Other investors included Sequoia, Fidelity, Andreessen Horowitz, Quiet Capital, VY and Snoop Dogg.

The announcement prompted criticism of Reddit for linking itself with a company from China, where the ruling Communist Party enforces extensive online censorship. Access to Reddit is blocked in China.

Tencent operates online games and popular WeChat social media service. It owns 40 per cent of "Fortnite" creator Epic Games and 15 per cent of photo service Snap.