'Most dangerous moment' in Ukraine crisis, says Johnson meeting with Nato chief – video

Boris Johnson has said the Ukraine crisis has entered 'the most dangerous moment' on a visit to Nato's headquarters as Russia continues its military buildup on the borders of its southern neighbour.

Military analysts estimate Moscow has massed more than 135,000 troops on the borders of Ukraine, both in Russia and in Belarus - and some now believe nearly all the necessary elements are in place if Putin wanted to attack.

Nato's secretary general, Jens Stoltenberg, said a political solution was still possible but warned Russia would 'pay a high price' if it chose confrontation

• Boris Johnson says Ukraine crisis has entered most dangerous moment'