TCS Group Holding PLC founder Oleg Tinkov, who has acute leukemia, resigned as chairman of the board of directors at Russia-based JSC Tinkoff Bank to focus on his health, the group said April 2.

Tinkov was replaced by Stanislav Bliznyuk, who resigned from the bank's management board following the appointment. Chief Information Officer Viacheslav Tsyganov will join the management board after receiving central bank approval.

Oleg Tinkov also transferred his stake in TCS to a family trust to ensure the shares are held by his family in the event of his death, Kommersant reported April 2. The move will help protect the bank and affiliated companies from $1 billion tax fraud charges Tinkov is facing in the U.S., the newspaper said.

Tinkoff Bank is fully owned by TCS Group Holding. Tinkov Family Trust owns 40.4% of the group following the recent ownership changes.