Saudi Crown Prince Mohammed bin Salman gave Vladimir Putin a high five in extraordinary scenes during the G20 leader's summit in Argentina.

Salman, who has been accused by the international community of ordering the killing of journalist Jamal Khashoggi, had been left standing alone as world leaders filed past him and into a meeting room - before the Russian President arrived.  

Putin, who has faced claims he ordered the nerve attack on Sergei Skripal in Britain, then held up his hand which the Saudi enthusiastically grabbed before they sat down with broad smiles on their face.

The Russian leader has also been put under increasing pressure in recent days after warships rammed, fired on, then seized three Ukrainian boats in the Kerch Strait in a serious escalation of tensions around Crimea.