Vladimir Putin’s shriveled hand at a public event in Russia has prompted a fresh wave of speculation about the dictator’s health. Footage of the Russian president captured at a conference last week shows the 73-year-old despot’s right hand looking sickly and visibly withered, covered in bulging veins and thin, wrinkled skin.

The statement marks the latest episode of nuclear sabre-rattling between the world's two largest atomic powers, after Putin and Trump failed to find ways to resolve the Ukraine conflict.

The US president, who is due to host Ukraine's Volodymyr Zelensky on Friday, says there will be fresh US-Russia talks with "high level advisors" next week.

An earlier proposed Trump-Putin summit in Hungary was scrapped when it became clear Russia would not agree to the U.S. president's demand for an immediate ceasefire in the Ukraine war.