A senior Moscow security official has rebuked United States President Donald Trump and raised the danger of another world war breaking out after Trump said Russian leader Vladimir Putin was ?playing with fire? by refusing to engage in Ukraine ceasefire talks with Kyiv.

Dmitry Medvedev said World War III was the only ?REALLY BAD thing? in a response, late on Tuesday, to Trump, who had earlier posted a message to Putin on social media saying ?really bad things would have already happened in Russia? without his intervention.

?What Vladimir Putin doesn?t realise is that if it weren?t for me, lots of really bad things would have already happened in Russia, and I mean REALLY BAD. He?s playing with fire,? Trump said in a post on his platform, Truth Social.

Medvedev responded on the platform X: ?Regarding Trump?s words about Putin ?playing with fire? and ?really bad things? happening to Russia. I only know of one REALLY BAD thing ? WWIII.?

?I hope Trump understands this!?

In response, US envoy Keith Kellogg quoted Medvedev?s post and said it was reckless.

?Stoking fears of WW III is an unfortunate, reckless comment? and unfitting of a world power,? Kellogg wrote on X.

Currently the deputy chairman of Russia?s Security Council and a key Putin ally, Medvedev served as the Russian president between 2008 and 2012, and is known for his sabre-rattling comments.

He has repeatedly warned, throughout Russia?s war on Ukraine, that Moscow could use its nuclear arsenal.

Putin also raised the possibility of nuclear confrontation in a state of the nation address in March 2024, warning Western powers of Russia?s nuclear capabilities should any decide to deploy troops in support of Ukraine.

?Everything that the West comes up with creates the real threat of a conflict with the use of nuclear weapons, and thus the destruction of civilisation,? Putin said at the time.

Medvedev?s public rebuke of Trump also comes after the US president said in a post on Sunday that Putin had ?gone absolutely CRAZY? by carrying out extensive aerial attacks on Ukraine despite widespread calls for a ceasefire and Washington?s frustrated attempts to broker a peace accord.

?I?ve always had a very good relationship with Vladimir Putin of Russia, but something has happened to him,? Trump posted on Sunday.

Trump also told reporters he was considering new sanctions on Russia amid the impasse in ceasefire talks.

The war of words on social media comes as hopes for a swift end to Russia?s war on its neighbour dim. Kyiv suffered another battlefield setback on Tuesday, with Russian forces capturing four villages in Ukraine?s northeastern Sumy region.

Sumy Governor Oleh Hryhorov wrote on Facebook that the villages of Novenke, Basivka, Veselivka and Zhuravka had been occupied by Russia, although residents had long been evacuated.

Russia?s Ministry of Defence said on Monday it had also taken the nearby village of Bilovody, implying a further advance into Ukrainian territory as the more than three-year war grinds on.

Ukrainian officials have said for weeks that Russian troops are trying to make inroads into the Sumy region, the main city of which lies less than 30km (19 miles) from the border with Russia.

Russian forces, attacking in small groups on motorcycles and supported by aerial drones, have been widening the area where they have been carrying out assaults on the front line, a spokesperson for Ukraine?s border guard service said.

Ukrainian forces last year used the Sumy region as a launchpad to push into Russia?s neighbouring Kursk region, where they captured a vast area of territory before being driven out by Russian forces last month. IALJAZEEZA)

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