PUTIN is preparing a “huge, vicious and unrelenting” revenge assault on Ukraine, US insiders have warned.

Kremlin officials have stated that a comprehensive response to last week’s remarkable Operation Spiderweb targeting four significant Russian airbases has not yet taken place, but they assure it is imminent.

The retaliatory attack is expected to be “asymmetrical,” incorporating both drones and missiles to hit notable Ukrainian locations, rather than solely military ones, a US official informed Reuters.

Another said the operation could begin within days.

A senior Western diplomat added: “It will be huge, vicious and unrelenting.

“But the Ukrainians are brave people.”

Last Friday, Russia launched an intense assault of missiles and drones on Kyiv, resulting in at least six deaths and over 80 injuries, yet American officials warn this may just mark the beginning.

Russia’s Defense Ministry called it a response to “terrorist acts” by Ukraine – but insiders say the real retaliation is still being assembled behind the scenes.

U.S. officials believe the SBU — Ukraine’s security service — may be directly targeted in the revenge strike.

Carnegie Endowment analyst Michael Kofman told Reuters: “Most likely, they will attempt to retaliate against (SBU) headquarters, or other regional intelligence administration buildings.

“In general, Russia’s ability to substantially escalate strikes from what they are already doing — and attempting to do over the past month — is quite constrained.”

PUTIN’S $7bn HUMILIATION

The looming storm follows Operation Spiderweb – Ukraine’s most daring covert strike yet.

It was led personally by spy chief Vasyl Malyuk under the direct orders of President Volodymyr Zelensky.

Over 117 kamikaze drones were launched from hidden mobile units disguised as everyday cargo trucks, slipped undetected into Russian territory.

New footage released on Saturday by Ukraine’s SBU shows an FPV drone lifting off from a lorry rooftop before smashing directly into a Russian bomber at the Belaya airfield.

The strikes hit four strategic bases – Belaya, Dyagilevo, Olenya, and Ivanovo — torching aircraft capable of launching nuclear warheads.

Ukrainian officials say 41 planes were destroyed or damaged.

U.S. intelligence puts the figure closer to 20, with at least 10 completely destroyed – still a staggering blow to Russia’s long-range bomber fleet.

The $7billion damage, inflicted with zero boots on the ground, has left the Kremlin tyrant furious and determined to reassert its military dominance.

‘IT’S NOT GOING TO BE PRETTY’

President Donald Trump revealed this week that he spoke directly with Putin on Wednesday.

In a post on Truth Social, Trump said the Russian despot told him “he will have to respond” to the drone attack.

Speaking to reporters later, Trump added: “It’s probably not going to be pretty. I don’t like it.

“I said: ‘Don’t do it. You shouldn’t do it. You should stop it.’

“But, again, there’s a lot of hatred.”

Meanwhile, Russia’s propaganda machine is framing the war as existential.

Putin spokesman Dmitry Peskov declared Friday: “This is about the future of our children, of our country.”

BLITZ ALREADY UNDERWAY?

While officials say the major strike is still to come, Ukraine is already reeling from a brutal few days of missile and drone attacks.

On Friday, 400 drones and 45 missiles rained down on cities across the country.

In Kyiv, explosions lit up the night sky near the Mother Ukraine monument.

A fire tore through the 11th floor of a residential block in Solomyanskyi, and emergency crews rushed to save civilians trapped inside.

Overnight into Saturday, Kharkiv suffered Russia’s largest airstrike yet, killing three – including a baby and a 14-year-old girl – and wounding 21.

“We have a lot of damage,” Kharkiv’s mayor Ihor Terekhov said.

At least 18 apartment buildings and 13 homes were hit, with more strikes reported in Donetsk, Dnipro, Ternopil, and Odesa.

Ukraine’s Air Force said it shot down 174 out of 206 drones and nine missiles overnight.

SUMMER OFFENSIVE BREWING

Western analysts say Mad Vlad is not just seeking revenge – but a breakthrough.

Reports from Ukrainian intelligence suggest up to 125,000 troops are massing near the Sumy and Kharkiv frontiers, with fears of a three-pronged summer assault to finally break the deadlock.

The offensive is expected to focus on Kramatorsk, Kostiantynivka, and Pokrovsk in the Donbas – with plans to encircle key cities rather than slug it out street by street.

Military analyst Konrad Muzyka told The Telegraph Russia’s tactics have evolved: “We have seen the Russians shift to focused, small-unit attacks, often of just three to five men.

“Company-size assaults of 50 to 100 men hardly ever happen anymore.”

But Ukraine, armed with drones and Western weapons, isn’t backing down.

Zelensky warned this week: “Even after all of Russia’s horrific attacks, he is reportedly preparing yet more so-called ‘responses.’

“With every new strike, with every delay of diplomacy, Russia is giving the finger to the entire world.”