Donald Trump says he has ordered two nuclear submarines to be positioned in the “appropriate regions” in a row with former Russian president Dmitry Medvedev.

It comes after Mr Medvedev, who is now deputy chairman of Russia’s Security Council, told the US president on Thursday to remember that Moscow had Soviet-era nuclear strike capabilities of last resort.

On Friday, Mr Trump wrote on social media: “Based on the highly provocative statements of the Former President of Russia, Dmitry Medvedev, who is now the Deputy Chairman of the Security Council of the Russian Federation, I have ordered two Nuclear Submarines to be positioned in the appropriate regions, just in case these foolish and inflammatory statements are more than just that.

“Words are very important, and can often lead to unintended consequences, I hope this will not be one of those instances. Thank you for your attention to this matter!”

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