MOSCOW — President Vladimir V. Putin, already a well established geopolitical star, had a splashy day on the global stage at the Group of 20 summit meeting on Friday, even by his own standards.

First, Mr. Putin stirred things up in Europe by proclaiming, in an interview with the Financial Times, that the world’s liberal political order had “outlived its purpose.”

Within hours, he listened cheerily through an apparent joke by President Trump about rubbing out journalists in Russia.

Later, a video of Mr. Putin shaking hands with an extraordinarily glum-looking Theresa May, the British prime minister, touched off another media storm.