Trump-North Korea talks: What's next?

The US Secretary of State Mike Pompeo is on his way home from North Korea, bringing with him three US prisoners. Their release is being seen as clearing a major obstacle to an unprecedented summit between the North Korean President Kim Jong Un, and Donald Trump. Mr Trump has tweeted that the detainees are due back later on Thursday, and he plans to meet them at the airport. Correspondent in Washington Simon Marks discusses the implications with Susie Ferguson.