David Cameron is "gravely concerned" at reports of Russian military vehicles crossing into Ukraine, his spokesperson said.
After speaking to Ukraine's President Petro Poroshenko, the Prime Minister said Russia must not use its humanitarian aid convoy as a pretext for provocation and asked Russia to "demonstrate willingness to find a peaceful solution to conflict in Ukraine."
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Joshua beat the older, more experienced boxer in front of 90,000 fans in Wembley Stadium.
Dry for most of the night. Rain in the southwest by dawn.
Host Paddy McGuinness tweeted a tribute to contestant Charlie Watkins whose date was featured in Saturday's episode.