Dianne Feinstein, chairman of the US Senate Intelligence Committee, has urged Russian President Vladimir Putin to "man up" and admit Russia made a mistake. She told CNN: "I think this has become a huge human drama, and I think the nexus between Russia and the separatists has been established very clearly, so the issue is where is Putin? I would say, 'Putin, you have to man up. You should talk to the world. You should say, if this is a mistake, which I hope it was, say it. I think the world has to rise up and say we've had enough of this. You cannot let this kind of thing happen, and Russia continues to prepare it for the next strike down of a civilian plane. There will be repercussions from this."