Secret documents uncovered Wednesday that Berlin has begun planning for the deployment of up to 800,000 NATO troops, including Americans, into Ukraine as tensions with Russia escalate, New York Post reported.

"Operation Deutschland" is a 1,000-page plan to prepare Germany for a potential World War III scenario.

According to the German daily Frankfurter Allgemeine Zeitung, the top-secret documents explain particular structures and infrastructure to safeguard so that the military may use them, as well as how companies and people can prepare in the event of heightened threats.

They also hinted that Berlin was planning to move 200,000 military vehicles across German soil if the alliance was forced to help Ukraine's operations, though additional specifics were kept confidential.

Germany also instructed individuals, through the documents, on how to prepare for the worst by increasing their self-sufficiency through methods, such as installing diesel generators or wind turbines.

The worry is not limited to Germany. Sweden and Norway have also lately released leaflets and material teaching residents how to prepare in case the Ukraine war spills over into their nations.

The growing fear comes as Russian President Vladimir Putin formally revised the Kremlin's nuclear strike doctrine on Tuesday, saying that Moscow may now deploy nuclear weapons to counter non-nuclear, "conventional weapons" attacks.

German Foreign Minister Annalena Baerbock said Tuesday that the country would “not let ourselves be intimidated” by Putin’s nuclear policy shift, citing he was "playing with our fear" and recalling the annexation of Crimea by stating that Germany made the mistake of not listening to its partners at the time.

“We must invest in our own security and protection,” she added.

Many foreign leaders, analysts, and US officials have stated that the direct deployment of US forces is the most significant escalation in the war yet, and Donald Trump has repeatedly warned that the US could be on the verge of World War III.

Trump backers took to social media on Sunday to voice their reactions to reports that President Joe Biden had authorized Ukraine to use US-supplied Army Tactical Missile System (ATACMS) missiles for strikes within Russian territory.  

"As President Trump has said on the campaign trail, he is the only person who can bring both sides together in order to negotiate peace, and work towards ending the war and stopping the killing," Trump Communications Director Steven Cheung told Newsweek.

Zelensky continued to laud the president-elect this week, telling Fox News on Tuesday that he believes Trump's election will bring the conflict to a conclusion sooner because he is "stronger" than Putin.

He warned, however, that if the US Congress refuses to provide military help to Ukraine, his nation "will lose".

Russia will respond in mirror-like fashion if Ukraine escalates: Putin

Meanwhile, Russian President Vladimir Putin said on Thursday that the war in Ukraine "previously provoked by the West, has acquired elements of a global nature."

Putin explained that in the case where systems such as Oreshnik are used in Ukraine, "we will offer civilians in advance, as well as ask citizens of friendly states located there to leave dangerous zones. We will do this for humanitarian reasons — openly, publicly, without fear of opposition from the enemy."

Russia will respond strongly and in a mirror-like fashion if Ukraine's aggressive escalation continues, Putin vowed. He warned the nations that are "hatching plans to use their military contingents against Russia" to also deeply consider his threat. 

He expressed that the United States made a mistake when it destroyed the pact on the elimination of intermediate- and shorter-range missiles (INF treaty) in 2019, under what he called "a far-fetched pretext," accusing of leading the world toward global conflict and holding it responsible for the destruction of the international security system.

He detailed how Russian troops are "successfully advancing along the entire line of the battle contact. All tasks that we set for ourselves will be accomplished."

Russia always ready to resolve issues peacefully

 Putin reaffirmed that Ukraine's use of long-range weapons would not change the course of the war. He revealed that Russia targeted the Yuzhmash complex in Dnipro, Ukraine, which manufactures missile technology, with a successful strike using the Oreshnik missile.

Oreshnik is Russia's newest hypersonic intermediate-range ballistic missile (IRBM), which Putin unveiled today.

He disclosed that the hit on Ukraine's Yuzhmash complex was carried out by a ballistic missile in a nuclear-free hypersonic mode and conducted in "combat conditions", explaining that "our missile engineers named it Oreshnik."

"The targets for striking during further tests of our newest missile systems will be determined by us based on the threats to the security of the Russian Federation." 

Putin emphasized Russia's readiness for peaceful resolutions but warned that any escalation would be met with a decisive response. "There will always be an answer," he declared, adding that Russia reserves the right to target military facilities of countries using weapons against it.

"We consider ourselves entitled to use our weapons against the military facilities of those countries that allow their weapons to be used against our facilities. We will respond decisively and proportionally in the event of an escalation of aggressive actions," Putin said. 

"We have always preferred and are now ready to resolve all disputed issues by peaceful means. But we are also ready for any development of events. If anyone else doubts this, they really should not. There will always be an answer," he warned.