A crescendo of electronic music overlaid with rap was sending 80 or so partying young Russians into a joyous ecstasy. And then the release that they had all been waiting for, led by the band.

“Vladimir Putin, he’s such a great political leader! Vladimir Putin, he is such a great warrior!” they screamed at the top of their voices before bursting into laughter.

“Irony. It’s ironic,” explained a young partygoer later, with a wry smile. “We can’t go any further than that.”

Kazan, 550 miles east of Moscow, had been described as a “hardcore Z city” by a source in St Petersburg before the Telegraph flew in to cover Putin’s Brics economic forum where he was entertaining African, South American and Asian leaders.

A wall of pro-war sentiment was expected in this city of wide boulevards lined with Tsarist-era buildings and a fortress that dominates the confluence of the Volga and Kazanka rivers.

So strong is Kazan’s “Z city” status that the Kremlin has chosen it as the site of a new factory to produce Shahed kamikaze drones under licence from Iran. The letter ‘Z’ has become a pro-war symbol in Russia.