LONDON: Britain will consider “increasing sanctions” against Russia following findings from five European states that opposition leader Alexei Navalny was killed by dart-frog toxin in a Russian prison, UK foreign minister Yvette Cooper said Sunday. “We continue to look at coordinated action, including increasing sanctions on the Russian regime,” Cooper told the BBC from the Munich Security Conference, where the UK, France, Germany, the Netherlands and Sweden announced findings that the Russian state was a prime suspect for poisoning Navalny two years ago.

There is no innocent explanation for the toxin, called epibatidine, being found in samples taken from Navalny's body, the Foreign Office said.

Navalny, who staged massive anti-Kremlin protests as President Vladimir Putin's fiercest foe, died in the Arctic penal colony in February 2024.