Russia has been warned that a major NATO-supported attack by Ukraine is imminent, according to State TV in Moscow.
It comes as Russia continues to pour troops and heavy military equipment into areas on the border with Ukraine.
The warning claims that the attack will be on the Pro-Putin region of Donbas which is currently controlled by rebels.
US intelligence previously warned that Russian secret services are preparing a fake video showing staged explosions and fake corpses.
This is allegedly to be used as a pretext for Vladimir Putin to launch war against its neighbour.
It is unclear if the concerted warnings across three staunchly pro-Kremlin TV channels in prime time evening bulletins was part of a Russian propaganda bid to engineer a “casus belli” - an act to provoke or justify war.
State-run Channel 1 warned that military intelligence of the Donetsk People's Republic (DPR) and Luhansk People's Republic (LPR) is "observing preparations by the Armed Forces of Ukraine for an offensive."
“Heavy artillery and hospitals are being deployed, and mobilisation reserves are being formed," it added.
NTV, owned by Gazprom-Media, told viewers: “Life along the contact line is becoming increasingly unbearable.
“Meanwhile, the Ukrainian army's artillery unit commanders have begun to reconnoitre terrain on the frontline in Donbas.
“In addition, the DPR territory has been shelled four times over the past 24 hours."
Meanwhile Rossiya 1 claimed "irrefutable evidence" had been found that NATO weapons were “already being used to carry out new attacks” including on a power station.
“This is not a [proper] war for the West, more likely a small war,”
“Kyiv has already deployed up to 120,000 security forces to the demarcation line in Donbas,” warned the channel, despite denials by Ukraine of any planned offensive.
In Russia’s Voronezh region, bordering Ukraine, a Pantsir-S anti-aircraft missile and gun complex has been stationed right next to a kindergarten, evidently highlighting the risk of war.
A video shows air defence units engaged in war games to repel a mock enemy of Su-34 warplanes in a situation “as close as possible to combat”.
Russia has strongly denied the US claims of a video featuring staged explosions and corpses, as well as actors, in a stunt to provide a pretext for invasion.
Putin’s spokesman Dmitry Peskov said: “They have said suchlike previously. But nothing of the sort happened.”
Russia’s permanent representative to the EU, Vladimir Chizov, said: “I can assure you that Russia is never involved in any business of this kind.”
Russia has also denied any intention of invading Ukraine, despite NATO warning of the biggest deployment of Moscow’s forces in Belarus since Soviet times.
“Over the last days, we have seen a significant movement of Russian military forces into Belarus. This is the biggest Russian deployment there since the Cold War,” said Secretary-General Jens Stoltenberg.
However, Ukraine also played down the threat of a Russian invasion.
Defence minister Oleksii Reznikov said “the threat exists, the risks exist, but they have existed since 2014, ever since Russia has become an aggressor.”
Currently, “there are no grounds for panic, fear, flight or the packing of bags”, he said.
And the head of the armed forces in Ukraine Valery Zaluzhny denied any plans for offensives by his country in the Donbas or Crimea.
"No orders or discussions about a military operation in Crimea and Donbass have been held,” he said.
UK foreign secretary Liz Truss said of the US false flag stunt claims: "This is clear and shocking evidence of Russia’s unprovoked aggression and underhand activity to destabilise Ukraine.
“This bellicose intent towards a sovereign, democratic country is completely unacceptable and we condemn it in the strongest possible terms.”
Belarus has protested to Ukraine after an alleged spy drone was downed on its territory.
New footage shows the drone for the first time.
Minsk claimed the unmanned reconnaissance flyer was on an illegal mission to monitor massing Russian troops near Brest.
“An analysis of data from the drone systems shows that it was launched from Ukrainian territory to accomplish an illegal reconnaissance mission over the Brestsky range [one of the ranges to host the joint Russian-Belarusian exercise]," said the Belarus foreign ministry.
Ukraine’s foreign ministry spokesperson Oleh Nikolenko denied launching the spy drone, claiming the story was “mythical”.
It was “another provocation by the authorities in Belarus… We urge Minsk not to play along with Russia's destabilising actions.
“Peace on the border between Belarus and Ukraine is in the interest of the entire region,” he said.
