Russian President Vladimir Putin sends signal to West with flight on nuclear-capable bomber

Russian President Vladimir Putin flew on a modernised Tu-160M nuclear-capable strategic bomber on Thursday, in a move likely to be seen in the West as a pointed reminder of Moscow's nuclear capabilities.

The giant swing-wing plane, codenamed "Blackjacks" by military alliance NATO, is a modernised version of a Cold War-era bomber that the former Soviet Union would have deployed in the event of nuclear war to deliver weapons at long distances.

State TV showed Putin clambering down a ladder from the plane after the flight and telling reporters it was a reliable and modernised aircraft that could be accepted by the Russian Air Force.

"It's a new machine, a lot about it is new. It's easier to control. It's reliable," said Putin.

The Russian leader, who is expected to easily win another six-year term next month, made the flight at a time when Moscow and the West are at odds over Russia's war in Ukraine and the death in prison of opposition politician Alexei Navalny.

Some Russian and U.S. diplomats say they do not remember a time of worse relations between the world's two biggest nuclear powers, including during the 1962 Cuban Missile Crisis.

State TV showed the giant plane, which Russia nicknames "White Swans", taking off and landing at a runway belonging to the factory in Kazan that makes the modernised supersonic aircraft, with correspondent Pavel Zarubin excitedly calling it "a unique event".

Kremlin spokesman Dmitry Peskov said the plane's flight path was a military secret. The flight with Putin aboard had lasted 30 minutes, Russian news agencies reported.

The Tu-160M, which has a crew of four, is capable of carrying 12 cruise missiles or 12 short-range nuclear missiles and can fly 12,000 km (7,500 miles) non—stop without refuelling.

Russia's nuclear doctrine sets out the conditions under which a Russian president would consider using a nuclear weapon: broadly as a response to an attack using nuclear or other weapons of mass destruction, or to the use of conventional weapons against Russia "when the very existence of the state is put under threat".