Reports of Russian troops in Ukraine 'irrefutable' says ex-Nato commander

Reports of Russian troops crossing the border into Ukraine are "somewhat shocking" and "irrefutable", according to former Nato Supreme Allied Commander James Stavridis.

"This is not hot air coming out of Brussels. This is lying coming out of Moscow", he told Jane O'Brien on the BBC's World News America programme.

Admiral Stavridis also spoke about US strategy in the battle against Islamic State, saying he believes the US will need to send 8-10,000 more troops into the region.

He is Dean of The Fletcher School at Tufts University and author of The Accidental Admiral.