US President Joe Biden blamed Russian President Vladimir Putin for the death of Russian opposition politician Alexei Navalny. “Make no mistake,” the 81-year-old US leader said before a crowded White House press corps briefing. “Putin is responsible for Navalny’s death.” He said, however, that “it is not known exactly what happened” Biden said he was “schocked but not surprised” at the news. The US president said Navalny was remarkable in his persistence in fighting against Putin over the years which had seen the opposition politician poisoned, arrested on trumped-up charges and put in solitary…