THREE NATO countries will build bunkers along the border with Russia as World War 3 fears continue to grow.
Europe has also been warned to ramp up weapons stocks to "war-time levels" in preparation for an impending battle against Vladimir Putin.
As a result of the carnage caused from the Russian President's two-year invasion of Ukraine, the defence ministers of Latvia, Lithuania and Estonia have agreed to take action to avoid a similar fate.
The trio of Baltic nations will construct an “extensive network of fortifications” along the borders with Russia to deter Putin invading their countries.
It's thought the total cost of the project will amount to €60million (£51.2million).
The construction will begin in Estonia, with its government planning some 600 bunkers grouped around the border crossing points of Narva in the north and Voru in the south, report.
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Susan Lilleväli at the Estonian Defence Ministry said the overall intention is to ensure readiness "to fight the enemy from the first metre and first hour."
"The war in Ukraine has shown that taking back already conquered territories is extremely difficult and comes at great cost of human lives, time and material resources," she said.
Estonia, Latvia and Lithuania have long been considered the most likely Russian targets for Putin should he look to attack NATO countries.
While Ukraine has managed to withstand the Moscow onslaught for years, it's likely the three small Baltic states would be overrun within a matter of days.
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"These installations serve, first, the purpose of avoiding military conflict in our region, as they could potentially change the enemy's calculus," Lilleväli added.
"Counter-mobility and fortification measures have played a significant role in wars in our region in history, for example in Finland, and as the war in Ukraine has demonstrated they are perfectly valid also in this century."
Should Putin attack the three NATO countries, the defence treaty's allies would be forced into military action with the Soviet state - including the UK and US.
The secretary-general of NATO has since warned Europe to ramp up levels of weapons production in order to counter the threat from Russia.
Jens Stoltenberg said: "We need to reconstitute and expand our industrial base" to increase deliveries to Ukraine and refill weapons stocks.
The NATO chief claims the 31 member treaty does not seek a war with Russia but pointed to Russia's invasion of Ukraine as proof that "peace in Europe cannot be taken for granted".
"If Putin wins in Ukraine, there is no guarantee that Russian aggression will not spread further," he told Germany's .
"Supporting Ukraine now and investing in NATO's own capabilities is our best defence."
But fears of World War Three were ramped up even more following mindblowing threats from former US President Donald Trump towards fellow NATO members.
The American politician said he would let Russia "do whatever the hell they want" to members of the alliance that don't pay enough for defence at a rally in South Carolina on Saturday.
NATO immediately intervened and criticised Trump for "putting American and European soldiers at risk".
"NATO remains ready and able to defend all allies," they fumed. "Any attack on NATO will be met with a united and forceful response.
"Any suggestion that allies will not defend each other undermines all of our security, including that of the US, and puts American and European soldiers at increased risk."
Trump's comments will likely increase anxiety in Europe about the US withdrawing military support from Ukraine should he be re-elected later this year.
The former president has also long criticised NATO, threatening to pull the US from the alliance, with one of his campaign commitments to "fundamentally" re-evaluate "NATO's purpose and mission".
But NATO expects the US to remain a strong and committed NATO ally "regardless of who wins the presidential election".
The White House described Trump's comments as "appalling and unhinged".
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"Encouraging invasions of our closest allies by murderous regimes endangers American national security, global stability and our economy at home," spokesperson Andrew Bates said in a statement on Saturday.
"Rather than calling for wars and promoting deranged chaos, President Biden will continue to bolster American leadership and stand up for our national security interests - not against them."