"While it's true that Kasparov plays chess almost as well as my iPhone, otherwise he's an idiot," Musk tweeted.
An American businessman also called Kasparov a "moron".
Earlier, Musk said that people living in eastern Ukraine prefer Russia.
He also proposed his own version of the settlement of the conflict around Ukraine, according to which Crimea remains part of Russia, and in the regions recently annexed to Russia, referendums are once again held under the supervision of the UN.
* An individual recognized as a foreign agent by decision of the Ministry of Justice of the Russian Federation dated May 20, 2022.