Russia's defence minister told President Vladimir Putin on Friday the first Avangard hypersonic missiles had been put into service, in a move hailed as a major coup for Moscow.
Analysts say Russia is the first country to put into combat service intercontinental ballistic missiles armed with hypersonic weapons that Putin said can travel 20 times faster than the speed of sound.
"The first missile regiment equipped with latest strategic missiles with the Avangard hypersonic glide vehicle entered service at 10 am Moscow time on December 27", Defence Minister Sergei Shoigu told a meeting in televised remarks.
He congratulated the military on what he said was a "landmark event for the country and the armed forces."
Shoigu reported to Putin when the missiles entered service, a defence ministry official told AFP.
Defence officials have earlier said that the first Avangard regiment was placed in the Orenburg region in the Urals.
"This is the first intercontinental ballistic missile with the hypersonic glide vehicle in the world," Vasily Kashin, a senior research fellow at Moscow's Higher School of Economics, told AFP.
"It's a major scientific achievement."
Moscow said that it showed the Avangard missiles to US arms inspectors in late November in accordance with the New START treaty, which is due to expire in 2021.
The missile does not violate the treaty.
Putin unveiled the new weapon during his state of the nation address in 2018, saying it would defeat all existing missile defence systems.
He said at the time the missile was highly manoeuvrable and flew at 20 times the speed of sound.
Senior officials later said the intercontinental projectile was considerably faster.
Officials said the missile during tests reached the speed of Mach 27, or roughly 33,000 kilometres per hour.
Mach 1 is a unit of measurement equivalent to the speed of sound.
In December last year, Deputy Prime Minister Yury Borisov claimed it was impossible to predict the missile's movements, which meant "missile defence is practically rendered obsolete."
"At this speed, not a single interceptor missile can shoot it down," Borisov said at the time.
Speaking in December last year, Putin praised the successful tests of the missiles.
"This is a great, wonderful gift to the country for the New Year," he gushed.
Russia boasts of developing a number of "invincible" weapons that surpass existing systems and include Sarmat intercontinental missiles and Burevestnik cruise missiles.
This week Putin said that Russia was no longer trying to catch up with the West on arms development.
"This is a unique situation in our modern history: they are playing catch-up with us," he said.
Shoigu has said that new Russian weapons allow Moscow to ensure the country's security without starting a costly new arms race with the West.
The New START, which caps the number of nuclear warheads well below Cold War limits, is the last remaining major arms control treaty between Russia and the United States.
Putin has called for the speedy renewal of the treaty and complained that Washington showed no genuine interest in conducting talks on extending it.
He has warned of "global catastrophe" if Washington keeps dismantling an international arms control regime.
The United States earlier this year withdrew from the Cold War-era Intermediate-Range Nuclear Forces (INF) treaty, which limited missiles that could hit European cities, after saying that Moscow was in violation.
Together with the INF treaty, New START was considered a centrepiece of superpower arms control.