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Sanctioned billionaire Roman Abramovich was in Turkey for the start of peace talks between Ukraine and Russia on Tuesday.
He was at the Dolmabahce Palace in Istanbul, where the talks are taking place, and listened to a speech by Turkish President Recep Tayyip Erdogan but it was not immediately clear what role he has, if any, in the ceasefire negotiations.
Mr Abramovich, the owner of Chelsea Football Club which is up for sale, was among a group of people who suffered symptoms consistent with poisoning after attending earlier peace talks in Ukraine.
The Russian oligarch, who is involved in negotiations between Kyiv and Moscow, is understood — along with at least two Ukrainian negotiators — to have developed red eyes, constant and painful tears and peeling skin on their faces and hands since the meeting at the beginning of this month.
Mr Abramovich, whose superyacht is also reportedly in Turkey, has had a number of his assets targeted by international sanctions after the Russian war in Ukraine began.
Other oligarchs' homes, yachts and businesses have been added to an expanding list of people and businesses hit by UK sanctions.
Ukrainian and Russian negotiators met on Tuesday for the first face-to-face talks in nearly three weeks, with Ukraine seeking a ceasefire without compromising on territory or sovereignty as its forces have pushed Russians back from Kyiv.
Mr Erdogan welcomed delegations from both sides to the palace and said “stopping this tragedy” was up to them. Ukrainian television reported that talks had begun with “a cold welcome” and no handshake.
Ukraine and the United States hold little hope of an immediate breakthrough. But the resumption of face-to-face talks is an important first step towards a ceasefire in a Russian invasion that is stalled on most fronts but inflicting horrible suffering on civilians trapped in besieged cities.
Ukrainian Foreign Minister Dmytro Kuleba said of the talks in Turkey: “We are not trading people, land or sovereignty.”
“The minimum programme will be humanitarian questions and the maximum is reaching an agreement on a ceasefire."
Kremlin spokesman Dmitry Peskov said talks so far had not yielded any substantial progress but it was important they continued in person.