So the rumours are true after all.

Chinese actress Zhang Ziyi, 40, has confirmed on social media that she is pregnant with her second child.

In a Weibo post on Monday evening (Oct 28), she said that she is currently in her 30th week of pregnancy and weighs 58kg, adding that her weight is still increasing. She also posted a photo of herself with the baby bump.

Zhang is married to Chinese rock singer Wang Feng, 48, and the couple have a daughter who will turn four in December. Wang has two other daughters from previous relationships.

There were rumours of her second pregnancy as early as April, when the actress was reportedly spotted with a slight baby bump with Wang at the Beijing airport. But neither Zhang nor Wang had confirmed the rumours until Monday.

The actress who shot to global fame with movie Crouching Tiger, Hidden Dragon (2000) wrote on Weibo that she is now in Japan for the 32nd Tokyo International Film Festival, which opened on Monday and will close on Nov 5.

She is the president of the festival's Competition Jury. The other four members of the jury are American film and television producer Bill Gerber, French actress and producer Julie Gayet, Danish film director Michael Noer and Japanese film director Ryuichi Hiroki.

Zhang said she and the other jury members will determine the winners of seven key categories for 14 movies in the next eight days.

She wrote: "Let me share the joy with everybody...Today, I have a special identity as a mother-to-be who insists on working as she loves her job and is dedicated to it...I am extremely proud of both identities. Thanks to everyone for your concern and support."