NATO has joined Germany and the US in condemning recent claims by Russian President Vladimir Putin that his country has developed a new, "invincible" nuclear weapon.

On Friday, NATO spokeswoman Oana Lungescu said: "Russian statements threatening to target allies are unacceptable and counterproductive." She also reiterated the fact that the alliance would remain vigilant in using its military forces to deter foreign aggression directed at members.

The statement from NATO echoed comments by German Chancellor Angela Merkel and US President Donald Trump, both of whom voiced concern about a speech delivered by Putin on March 1, in which he spoke of Russia's buildup of nuclear weapons, a German government spokesman said on Friday.

"The chancellor and the president are ... concerned about Russian President Putin's latest remarks about arms developments and their negative impact on international arms control efforts," Steffen Seibert said in a statement summing up a phone call between Merkel and Trump on Thursday.

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An 'irresponsible' presentation?

In a state of the nation address on Thursday, Putin said Russia had tested new nuclear weapons, including a nuclear-powered cruise missile that he described as "invincible."

The Russian president also warned that the military buildup would be able to cancel out NATO's amassment of military force on Russia's borders, though he stressed that Russia did not intend to attack any other country.

Putin's speech featured an animation that showed missiles striking parts of the United States, a presentation that the US State Department described as "irresponsible."

The Kremlin has rejected US claims that it is in breach of arms control treaties with its new weapons and denied that Putin's speech marked the start of a new arms race.

The animation showed missiles striking the US eastern seaboard

Call for Syria ceasefire implementation

Merkel and Trump also agreed that Syria's regime and its Russian and Iranian allies should "promptly and fully implement" a recent US Security Council resolution calling for a 30-day ceasefire in Syria, Seibert said.

The two leaders called on Moscow to stop participating in the assault on eastern Ghouta, a rebel-held suburb near the capital, Damascus, in which more than 550 people have been killed.

They also demanded that the government of Syrian President Bashar al-Assad be held accountable for the use of chemical weapons, attacks on civilians and the humanitarian blockade.

tj/kms (Reuters, AP, AFP)

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