US Secretary of State Marco Rubio said Washington hopes to convince Beijing to play a “more active role” in resolving the Iran crisis, a clear sign the issue will come into sharp focus when President Donald Trump holds his closely watched summit with Chinese leader Xi Jinping. Speaking to Fox News aboard Air Force One, Rubio said the Iran war was a “huge source of instability” and “threatens to destabilise Asia more than any other part of the world because it’s heavily reliant on the straits for