Poland has begun building a £1.9billion ‘East Shield’ along its borders with Russia and Belarus, in an effort to protect NATO’s eastern flank as tensions simmer amid the war in Ukraine.

The 400-mile-long construction will include anti-tank fortifications, bunkers and other obstacles built to physically defend the border and control movement at a time when US support for Europe’s defence is expected to wane as Donald Trump takes office in January.

Trump, who last week won the US presidential election, has repeatedly said he would ‘end’ Russia’s invasion of Ukraine on his first day in office, adding that he also plans on cutting aid to Kyiv, despite the US being a top financial and military backer. His team has also reportedly considered the idea of creating an 800-mile buffer zone across the front line that would be marshalled by EU and UK troops.

Anti-drone systems and state-of-the-art surveillance technologies, powered by artificial intelligence to help early threat detection, will also protect Poland from threats posed by modern warfare revealed by the conflict to the south.

What’s more, the ‘shield’ will also include a satellite component in order to provide ‘another element of safety in space,’ Poland’s Prime Minister Donald Tusk said, in order to ready the country for ‘the wars of the future’.

The fortifications are designed to fend off potential threats from ‘the enemy’, Tusk said earlier this year, with the heavily militarised Russian exclave of Kaliningrad to the north considered to be posing a growing threat to the West.

According to details provided by the government, the programme, perhaps the most significant national security investment in Poland’s post-war history, will employ modern surveillance equipment, including imagery intelligence (IMINT), signals intelligence (SIGINT), and acoustic monitoring to improve situational awareness.

The multi-layered line of defences is expected to be around 200 metres deep, consisting of fences, ditches and minefields.

A high border fence will provide the first barrier to any invaders, followed by barbed wire and anti tank trenches.

Obstacles including ‘dragon’s teeth’ – concrete pointed blocks used to stop the movement of armoured vehicles – will also be placed in the way.

Bunkers and underground shelters will also be concealed within forests to protect those inside the border should the defences fail.

The project was announced in response to Russia’s illegal war in Ukraine and what the Polish government labels ‘hybrid war’ tactics by Belarus and Russia.

These include increase migratory pressure on the eastern border, with Warsaw claiming that Minsk and Moscow may be colluding to funnel asylum seekers westwards, putting a strain on western countries and fuelling divisive rhetoric.

‘The border cannot be crossed with impunity… It is Russia and Belarus behind this procedure, and the whole world calls it a hybrid war. We will not back down,’ Tusk said back in July.

‘We do this to deter the enemy, so that all those who wish Poland ill, all those who plan an attack, an aggression against our allies or against our country, hear here today, from the Krakow Main Market Square: stay away from Poland!’ Tusk said at an event marking the launch of the initiative back in May.

He added: ‘Poland is strong, Poland will be safe thanks to its own actions and thanks to its own allies.’

Poland has the highest military spending per GDP out of all NATO member countries, according to a recent report by the defence alliance. Its ambitious project is set to be completed by 2028.

Meanwhile another project, set to begin in 2025, is being planned by NATO members Estonia, Latvia and Lithuania, who announced a ‘Baltic Defence Line’ in January.

The countries’ shared concerns over the threat posed by Russia will see it integrated into Poland’s eastern defence efforts.

They are seeking EU funding to build a network of bunkers, barriers, distribution lines and military warehouses along their borders with Russia and Belarus, Estonian officials said in September.

‘The need for a (Baltic) defence line stems from the security situation and supports NATO’s new forward defense concept,’ Estonian Defense Minister Hanno Pevkur said in a statement.

‘At the same time, it strengthens the security of the European Union and the military defence of its borders, which is why we clearly see that the EU could also financially support the project,’ he went on.

Defence ministers from the four countries said that threats at the Baltic-Polish frontier are rising and that ramping up fortifications ‘remains a high-priority contributing to our pledge to defend every inch of (NATO) territory.’

‘Russia’s war against Ukraine has shown that creating physical obstacles on an open ground with no natural defensive cover is paramount even in technologically advanced warfare,’ they said in a joint statement.

Lithuania has recently blocked and fortified a bridge over the Nieman river which links it to the Russia’s Kaliningrad, with officials saying they planned to fortify and even mine other bridges connecting their country to the exclave.

The small but heavily armed territory is lodged between the Baltic Sea, Poland and Lithuania, and hosts the headquarters to Russia’s Baltic Sea Fleet.

‘Kaliningrad is essentially a Russian weapons depot, and it has a lot of militarily operational equipment in use, not just in storage,Senior Fellow Atlantic Council Fellow Elisabeth Braw told the Kyiv Independent earlier this year.

Russia’s invasion of Ukraine escalated fears that the territory’s neighbours could be the first to be targeted in the event of a war between Moscow and NATO.

Poland’s foreign minister claimed in June that Russia could be storing up to 100 nuclear warheads in the territory.

‘If you look at the world from Warsaw, the Russian enclave of Kaliningrad is 200 km to the north, and there are 100 nuclear warheads, and the Russians keep them there. Besides, Belarus is nearby. That means that an attack on the European Union is absolutely probable,’ Radoslaw Sikorski warned.

He also pointed out that Russian missiles aimed at Ukraine have, on occasion, violated the airspace of Poland.

‘Sometimes they accidentally fly into our airspace. Even to the western part of Poland, which is 250 km from here. It is very close, and the danger is greater than some people think.’

Earlier this year, Western intelligence claimed that a secret electronic weapon used to jam GPS technology on flights and ships is based there.