Russia will produce only a few units of a hypersonic weapon that President Vladimir Putin had bragged was already in serial production, according to people with direct knowledge of a U.S. intelligence report.

The Kremlin is having a hard time finding a source for the critical carbon fiber components needed to produce the weapon, a hypersonic glide vehicle dubbed Avangard.

It was one of the six weapons Putin boasted about in March 2018. At the time, the Russian leader claimed Avangard was capable of reaching targets at a speed of 20 times the speed of sound and that the weapon can strike “like a fireball.” He also said that the device had already entered serial production.

In October, CNBC learned that the Kremlin was looking for another carbon fiber source since their current supply was unable to withstand the extreme temperatures of hypersonic flight. According to a U.S. intelligence report curated a month ago, the Kremlin has still not been able to find an alternative carbon fiber material.

“It’s expected that they will make no more than 60 of these hypersonic weapons because it’s just proving to be too expensive to develop,” one person told CNBC on the condition of anonymity. Read more

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Russia will produce only a few units of a hypersonic weapon that President Vladimir Putin had bragged was already in serial production, according to people with direct knowledge of a U.S. intelligence report.

Russia will produce only a few units of a hypersonic weapon that President Vladimir Putin had bragged was already in serial production, according to people with direct knowledge of a U.S. intelligence report.

Russia will produce only a few units of a hypersonic weapon that President Vladimir Putin had bragged was already in serial production, according to people with direct knowledge of a U.S. intelligence report.