VLADIMIR Putin has defied Donald Trump’s ultimatum and unleashed a fresh blitz on Ukraine.

The bombing came just hours after the US president warned the Russian tyrant of devastating sanctions and a flood of Nato weaponry unless Moscow agrees to peace in 50 days.

The Kremlin hit back with chilling threats and another deadly wave of attacks across war-ravaged Ukrainian cities – from Kharkiv to Zaporizhzhia and Sumy.

In Sumy Oblast, Russian drones deliberately targeted a university, injuring six people including a 19-year-old student and 14-year-old girl.

A separate missile strike in Shostka wounded another teen and damaged a medical facility.

Across Ukraine, at least five people were killed and 53 wounded in 24 hours, according to regional authorities.

Victims include a 63-year-old woman in Dnipropetrovsk, a 57-year-old woman in Kharkiv, and civilians in Donetsk, Kherson and Zaporizhzhia regions. Among the injured were four children.

In Kharkiv, a 68-year-old woman was hurt during night shelling.

Meanwhile, Kyiv launched its own counterstrikes.

Ukraine staged attacks on military facilities deep inside Russia with a new drone strike on Energiya enterprise at Yelets in Liuptsk region – which makes the chemical-based power sources for multiple Russian weapons including Iskander-M ballistic missiles.

Residents reported explosions and footage indicated the plant had been hit in a barrage of a dozen drones.

In Voronezh, a Ukrainian drone strike reportedly wounded 15 Russians, including a one-year-old baby.

The bombardments come amid chilling speculation that the US may have urged Ukrainian President Volodymyr Zelensky to pressure Putin by striking Moscow directly.

According to The Washington Post, Zelensky reportedly replied: “We can if you give us the weapons.”

Kyiv now has access to longer-range ATACMS missiles, capable of hitting targets up to 200 miles inside Russia.

US-supplied Tomahawk cruise missiles, with the range to strike the Russian capital, are reportedly still under consideration.

Trump’s ultimatum, announced alongside Nato chief Mark Rutte at the White House, greenlights a $10billion arsenal of long- and short-range missiles for Ukraine, largely funded by Europe and Canada.

He warned Putin of “very severe” 100 per cent tariffs if Moscow fails to negotiate within 50 days.

“I’m disappointed in him, but I’m not done with him,” Trump later told the BBC on Monday.

Matthew Whitaker, permanent US Representative to NATO, insisted the Trump about turn on arms supplies to Ukraine will bring peace.

“What this says to Vladimir Putin is very loud and clear which is – we have given you a chance for peace.,” he said.

“President Trump is a peacemaker, but if you want war, we will arm Ukraine – and Europe will pay for it. It’s actually a great step in ultimately bringing this war to a conclusion, to an end.

“In the last 18 months Russia has gained about one per cent of Ukrainian land. They are making no success, they are losing thousands of soldiers every single day.”

But Putin’s cronies dismissed Trump’s warning, with top Russian propagandist Aleksandr Sladkov saying: “Trump is trying to scare us with missiles, but this is difficult to do… Trump should be scared.”

“Everyone is trying to push us to turn Kyiv and Lviv into Hiroshima and Nagasaki.”

Sladkov warned that any US-led missile assault on Russia could trigger the launch of Yars, Moscow’s main land-based nuclear weapon, with warheads up to 20 times more powerful than the bomb dropped on Hiroshima.

“Imagine our country under attack by American cruise missiles, like Yugoslavia, Iraq, etc. I am sure that the Yars should go in response,” he declared on Russian state TV.

Meanwhile, former Russian president Dmitry Medvedev mocked Trump’s deadline as “theatrical,” writing on X: “Trump issued a theatrical ultimatum to the Kremlin. The world shuddered, expecting the consequences. Belligerent Europe was disappointed. Russia didn’t care.”

Kremlin-backed broadcaster Vladimir Solovyov went on to claim NATO’s support for Ukraine means Russia is in “a full-scale war”.

“We are already at war. It cannot be avoided… We are not fighting in Ukraine, we are fighting with NATO,” he fumed.

“The [Western] task is to destroy our country… Understand this already.”

And ultranationalist MP Leonid Slutsky brushed off the renewed arms push: “This will certainly be a step back, but will not fundamentally change the situation on the front… The goals of the [war] will be achieved in any case – either through negotiations or on the battlefield.”

But analysts say Trump’s 50-day timeline is no accident.

Kremlin expert Nikolai Starikov believes it’s timed to corner Putin during his planned visit to China.

“The White House’s plan is to disrupt the deepening of the strategic partnership between China and Russia,” he said.

That timing could also pressure Xi Jinping to lean on Putin to seek a peace deal – or face secondary sanctions that would hit Chinese interests.