Ukraine Russia crisis: where to from here?

The Russia - Ukraine crisis deepens by the day. 100,000 Russian troops, tanks and artillery have massed on Ukraine's borders in recent weeks, prompting fears of an invasion - despite repeated Russian denials of any plan to attack. Meanwhile the UK's government has come into lockstep with US and other allies to freeze assets and ban travel in the event of a Russian incursion into Ukraine. Russia alleges that U.S. leaders have broken promises they made in the early 1990s to not expand NATO's membership eastward. The U.S. and NATO leaders say no such pledges were made and refuse to discuss limitations on NATO's future expansion. So what, if any, prospects exist for a solution to this impasse? Kathryn speaks with Sir Adam Thomson, Director of the European Leadership Network. He's a former UK Permanent Representative to NATO; British High Commissioner to Pakistan, and Ambassador and Deputy Permanent Representative to the United Nations in New York.