Factbox: Kremlin foes who have suffered mysterious fates

FILE PHOTO: Russian opposition politician Alexei Navalny takes part in a rally to mark the 5th anniversary of opposition politician Boris Nemtsov's murder and to protest against proposed amendments to the country's constitution, in Moscow, Russia February 29, 2020. REUTERS/Shamil Zhumatov

LONDON (Reuters) - Kremlin critic Alexei Navalny, who is in intensive care in a Berlin hospital, was poisoned with a Soviet-style Novichok nerve agent in an attempt to murder him, German Chancellor Angela Merkel has said.

That has prompted some politicians and diplomats in Germany to suggest a European response involving the Nord Stream 2 gas pipeline.