At least three people were killed in the assault on the capital, and at least one died and 10 were wounded in a separate strike in the southern city of Zaporizhzhia.

Russia said on Monday it had downed nine Ukrainian drones that tried to attack part of the infrastructure of the TurkStream gas pipeline, through which Russian gas flows to Turkey and Europe, and called the attack an "act of energy terrorism".

Russia’s war on Ukraine has been dictated as much by events in the air as by territorial gains on the front line.

While Moscow and Tehran have shared warmer relations for decades, a revival of the nations’ allyship occurred when the former invaded Kyiv.

Just three days before US President-elect Donald Trump returns to the White House, Russia and Iran have finally signed a “comprehensive partnership agreement,” a deal that had been in the works for months.

The two countries sign a 20-year treaty covering areas ranging from defence and technology to energy and trade.

Iranian President Masoud Pezeshkian has arrived in Russia for the signing of a broad cooperation treaty as his country grapples with growing economic problems and other challenges