Abramovich has apparently been jetting between Istanbul, Moscow and Kyiv to relay messages to Vladimir Putin and Volodymyr Zelenskyy.
Roman Abramovich has been rumoured to have been involved in peace talks between Ukraine and his native Russia for several weeks.
Days after the conflict began more than a month ago, the Chelsea owner’s spokesman said the billionaire “had been contacted by the Ukrainian side for support in achieving a peaceful resolution”.
Just a few days ago, the Kremlin admitted for the first time that he did take part in early peace talks.
There have been reports that Mr Abramovich has been jetting between Istanbul, Moscow and Kyiv to relay messages back and forth from Vladimir Putin and Volodymyr Zelenskyy.
And on Monday it was revealed Mr Abramovich and two other negotiators were victims of a suspected poisoning after taking part in peace talks in Kyiv in early March.
So just how involved in the peace process is Mr Abramovich?
A spokesman for the Chelsea owner said: “I can confirm that Roman Abramovich was contacted by the Ukrainian side for support in achieving a peaceful resolution, and that he has been trying to help ever since.”
His involvement followed a request from the Ukrainian film producer Alexander Rodnyansky who had asked for help from individuals linked to Russia.
“Although Roman Abramovich’s influence is limited, he is the only one who responded and taken it upon himself to try,” Mr Rodnyansky said.
The Chelsea owner attended talks in the Ukrainian capital Kyiv. According to The Wall Street Journal, he was acting as a “peacemaker”.
Investigative media group Bellingcat said the negotiations lasted until about 10pm.
Three members of the negotiating team went to an apartment where they began feeling initial symptoms, including eye and skin inflammation.
“The symptoms did not abate until the morning,” the site said.
Mr Abramovich and two other negotiators drive from Kyiv to the western Ukrainian city of Lviv, before heading to Poland and then Istanbul to continue negotiations.
According to German newspaper Bild, the billionaire was part of a meeting between Sergei Lavrov, the Russian foreign minister, and Dmytro Kuleba, his Ukrainian counterpart.
The oligarch entered and left via a side door to avoid being spotted, the paper wrote.
Mr Abramovich is reported to have landed in Moscow after apparently being seen at an airport in Israel.
A jet linked to the Russian-Israeli billionaire landed in the Russian capital after a brief stop in Istanbul, en route from Tel Aviv, according to Flightradar24.
Dmitry Peskov, the Kremlin press secretary, admitted Mr Abramovich did take part in early peace talks between Ukraine and Russia.
However, Mr Putin’s spokesman insisted he was no longer attending the summits, which were being left to diplomatic teams from the warring nations.