Putin said it was “a pity” that he had not been able to have a proper meeting with Trump at the G20. “I think that one is really necessary. I hope that we can meet when the US side is ready for it.”

The Russian leader had a more productive dialogue in Buenos Aires with Saudi Crown Prince Mohammed bin Salman.

He greeted the crown prince as a long-lost friend — ignoring Western opprobrium over the prince’s alleged role in the murder of a dissident Saudi journalist in October.

Russia and Saudi Arabia are the world’s two leading exporters of crude, and Putin said they had agreed to extend a pact on oil production cuts, as prices slump on global markets.

That will resonate on the markets when trading in “black gold” resumes on Monday, as will the ceasefire to Trump’s trade war with China.