The European Union's diplomatic chief Josep Borrell on Monday called on the Russian authorities to launch an "independent and transparent investigation" into the apparent poisoning of Kremlin critic Alexei Navalny.
"The European Union strongly condemns what seems to be an attempt on Mr Navalny's life," said Borrell, speaking hours after the German hospital treating the Russian campaigner said their tests indicated he had been poisoned.
"It is imperative that the Russian authorities initiate an independent and transparent investigation on the poisoning of Mr Navalny without delay," his statement added.
"The Russian people, as well as the international community, are demanding the facts behind Mr Navalny's poisoning. Those responsible must be held to account."
Earlier Monday, the Charite hospital in Berlin said its clinical tests on Navalny "indicate poisoning with a substance from the group of cholinesterase inhibitors".
Hours later, a senior Russia doctor in the team that treated Navalny in Siberia said they had not detected that toxin in their tests.
Borrell's statement echoed one earlier Monday from German Chancellor Angela Merkel, who said those behind Navalny's poisoning "must be held accountable". She too called for a thorough and transparent investigation.