Russia has tested the world's most powerful vacuum bomb, which unleashes a destructive shockwave with the power of a nuclear blast, the military said on Tuesday, dubbing it the "father of all bombs".

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"Test results of the new airborne weapon have shown that its efficiency and power is commensurate with a nuclear weapon," Alexander Rukshin, Russian deputy armed forces chief of staff, told Russia's state ORT First Channel television. The same report was later shown on the state-sponsored Vesti channel.

"You will now see it in action, the bomb which has no match in the world is being tested at a military site."

It showed a Tupolev Tu-160 strategic bomber dropping the bomb over a testing ground. A large explosion followed.

Pictures showed what looked like a flattened multi-storey block of flats surrounded by scorched soil and boulders. "The soil looks like a lunar landscape," the report said.

"The defense ministry stresses this military invention does not contradict a single international treaty. Russia is not unleashing a new arms race."

Such devices generally detonate in two stages. First a small blast disperses a main load of explosive material into a cloud, which then either spontaneously ignites in air or is set off by a second charge.