US President Joe Biden rejected Russian leader Vladimir Putin's threat of war with the West if Ukraine's allies allow him to use their weapons to attack targets deeper inside Russia, reports "Euronews". 

The BBC reports that at last night's meeting in Washington, US President Joe Biden and British Prime Minister Keir Starmer did not make a decision to allow Ukraine to use long-range missiles to target Russia.

"The United States is committed to helping Ukraine defend itself against Russian aggression. Make it clear that Putin is not going to win this war. The people of Ukraine will win," Biden said, without referring to the West and long-range missiles.

Asked what he thought of Putin's threat, Biden replied: "I don't think much of Vladimir Putin."

Starmer did not mention the missiles even in brief comments before the official talks began, saying only that Ukraine was an important topic and: "I think the next few weeks and months could be crucial. It is very, very important that we support Ukraine in this vital war for freedom."

Starmer's comments come two days after Britain's Guardian newspaper reported that the US and UK had decided behind closed doors to allow Ukraine to use partly British-made Storm Shadow missiles to strike targets deeper inside Russia.

Two U.S. officials said on condition of anonymity that they believe Starmer is seeking Biden's approval to allow Ukraine to use the missiles because some of their components are made in America.

The US, concerned about any moves that could lead Russia to escalate the conflict, has moved cautiously before approving a series of earlier requests from Ukraine for specific weapons, including advanced tanks, missiles and F-16 fighter jets.

Meanwhile, at the United Nations in New York, Moscow's ambassador told the Security Council that NATO would wage "direct war" against Russia if approval was given to use weapons donated by the West to attack Russia.

"In this case, we will have to, as you understand, take the appropriate decisions with all the consequences of what the Western aggressors would do," Vasiliy Nebenzya said.

"We're not talking about a game here. The facts are that NATO will be a direct party to hostilities against a nuclear power. I don't think you should forget about this.

The remarks echoed comments by Vladimir Putin in St. Petersburg on Thursday, in which he warned the West of consequences if Kiev gets the permission it is seeking.

That prompted at least one Russian newspaper, Kommersant, to report that "Putin has drawn his red line" on its front page on Friday.

But despite warnings from the Kremlin, Ukrainian President Volodymyr Zelensky remained adamant that permission to attack military targets in Russia was key to turning the tide of the war.

Speaking at the Yalta European Strategy meeting in Kiev, he said Putin did not need approval to hit targets in Ukraine.

"When we hear that new missiles have arrived in Russia from Iran, it is the same evil that the allies have already had to shoot down in the skies of the Middle East," he said.

"If allies are jointly shooting down missiles and drones in the skies above the Middle East, why is there still no similar decision to jointly shoot down Russian missiles and Iranian Shahedi [drones] over Ukraine?"