We all know what's it's like to be left without a seat on public transport.

But an elderly commuter in China's Nanjing city took matters into her own hands last week when she sat on a young man's lap after he refused to give up his seat her on train.

The video, filmed on September 5, shows a woman asking a young man to give up his seat, saying: "I am an elderly woman and this seat is for people who are unable to stand."

When the man refuses, she decides to sit his lap directly.