Russian President Vladimir Putin has revealed new nuclear weapons he said could hit any target around the globe with little chance of interception.

Putin warned during his annual state of the nation speech on Thursday that an attack on Russia or any of its allies would elicit an immediate response from Moscow.

Video footage of the new weapons was projected behind him at a conference hall in the Russian capital, where Putin spoke with legislators.

He said the updated arsenal included a new intercontinental ballistic missile, a small nuclear warhead that could be attached to cruise missiles, underwater nuclear drones, supersonic arms, and a laser weapon.

Russia and the West are at odds in several conflicts - including Syria, where Russia supports President Bashar al-Assad - and Ukraine.

Russia annexed Crimea from Ukraine in 2014 following an invasion that resulted from the popular overthrow of the pro-Kremlin government in Kiev.

Russia-backed rebels continue fighting Ukrainian forces in the country's east. The United States and its allies have responded with punishing sanctions.

"They have not succeeded in holding Russia back," Putin said, referring to the West. "Now they need to take account of a new reality and understand that everything I have said today is not a bluff."

The remarks came shortly before a national election on March 18, which Putin is expected to win.

US toughens nuclear posture

The US has also taken a more aggressive stance on nuclear weapons under President Donald Trump. The Trump administration has called for increased spending to modernise its nuclear arsenal.

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The National Nuclear Security Administration, which oversees the US nuclear weapons programme, recently announced plans to resume production of plutonium pits, a necessary component of nuclear weapons.

The US also began work on smaller nuclear weapons under former President Barack Obama. Critics of these smaller nukes say their smaller payloads might make them more tempting to use.

Putin expressed concern over the US' new posture towards nuclear arms, saying the Russian nuclear programme was only for defensive purposes.

"We will view any use of nuclear weapons against Russia or its allies - be it of small, medium or any force - as a nuclear attack on our country," Putin said.

Meanwhile, Russian Defence Minister Sergey Shoigu suggested elements of NATO's anti-missile system deployed in Poland, Romania, and Alaska were penetrable.

"It turns out that the anti-missile umbrella has holes in it," Interfax news agency quoted Shoigu as saying on Thursday.

Shoigu also said NATO countries were trying to drag Russia into a new arms race, but its new nuclear weapons would help to avoid this scenario.

The Pentagon downplayed Russia's announcements, saying Moscow's weaponry was long under development and had already been factored into US assessments.

"We're not surprised by the statements and the American people should rest assured that we are fully prepared," said Pentagon spokeswoman Dana White.