Could North Korea Test H-bomb in Pacific?

As the war or words between Kim Jong-un and Donald Trump escalates, the North Korean foreign minister, Ri Yong-ho, has suggested that Pyongyang is considering the 'strongest hydrogen bomb test in the Pacific'. We ask Professor Vipin Narang, and expert in nuclear proliferation and strategy at the MIT, how seriously we should take North Korea's H-bomb threat?

Also in the programme: How Germany's response to the refugee crisis is playing into their election; Uber banned from London

(Photo shows: The North Korean leader Kim Jong-un responding to US President Donald Trump's statement at the UN. Credit: Reuters/KCNA)