"I can only congratulate the decision by Ukraine's top seeded player Elina Svitolina not to participate in a commercial tennis tournament in Moscow. There is always something more important than money. Respect!" he said.
The Moscow River Cup tournament is being held in the Russian capital from July 22 to 29.
As reported, world No. 5 Svitolina retained her position in the updated rating of the Women's Tennis Association (WTA).