Ewan McGregor's fight for child refugees

As world leaders begin arriving in New York for the 71st annual UN General debate, this year, for the first time, the gathering will include a high-level summit on migrants and refugees.

It is an issue close to the heart of the actor, Ewan McGregor, who was in northern Iraq last month.

In an exclusive interview, the BBC's Laura Trevelyan has been speaking to him in New York.