Video that is being distributed rapidly/ The condition of the president worsens, Putin's critical moment, his legs are shaking, experts tell what is happening to him: Possible signs of serious illness of...

This is the moment when Vladimir Putin's legs appeared to be shaking during a meeting, while experts assess it as a possible sign of Parkinson's disease. The Russian president, 70, who is said to be "seriously ill", met with Kazakhstan's President Kassym-Jomart Tokayev, 69, on Monday.

During the tense talks in Moscow, Putin's legs clenched together - a symptom of Parkinson's disease. He was also seen clutching his right arm with his left hand during talks - months after he was photographed walking along a red carpet with his right arm hanging limply by his side.

During Monday's tense meeting, Putin and Tokayev exchanged documents with a brief handshake and eye contact — but only for a second. After exchanging signatures on a document marking 30 years of diplomatic relations.