Prince William has spoken of the moment he was "tipped over the edge" following "traumatic" callouts as an air ambulance pilot.

The Duke of Cambridge talked at a conference in London that aimed to address mental health issues in the workplace.

He said he worked on several jobs in the east of England involving hurt children, including one that left him feeling "very sad and very down".

He added that speaking to people helped him cope with the "enormous sadness" that he had witnessed.