Chinese actress Zhang Ziyi's love for her son is so strong that she apparently developed a double chin from kissing him.

On Monday (April 12) morning, Zhang posted on Weibo a photo of her smooching the toddler, who turned one in January.

The 42-year-old wrote: "I am serious about kissing my son, proven by the double chin brought on by love. Will miss him on my working trip."

Zhang is married to rocker Wang Feng, 49, and the couple also have a five-year-old daughter.

Wang has two more daughters from a previous marriage and relationship.

Zhang, known for her roles in movies such as Crouching Tiger, Hidden Dragon (2000) and The Grandmaster (2013), took a break from acting after she became pregnant with her son. She was most recently seen in The Rebel Princess - her first TV series - which was filmed in 2018.

Several netizens praised Zhang for her motherly love, with some saying they would not mind Zhang gaining weight and developing a double chin.

Zhang posted four photos of herself on Monday night, writing: "I still miss him, but the double chin is gone."

Zhang did not give any details about her latest acting assignment, but she tagged the post in The Bund, Shanghai.