In the shadow of derelict, Soviet-era factories on the outskirts of Tallinn, Nato’s “Baltic backbone” is being forged with British steel and EU funds.

Braced against sub-zero temperatures, Estonian workers are building the first leg of a 500-mile, high-speed railway that aims to link up the Baltic capitals with Warsaw by 2030.

Rail Baltica, a multibillion-euro project, was first planned as a symbol of Estonia’s pro-Europe destiny after the collapse of the Soviet Union and its later accession to the EU and Nato in 2004.

But since Russia’s 2022 invasion of Ukraine, the railway has taken on a new and crucial purpose: if war breaks out between Moscow and Nato, it will be used to rapidly transport troops and equipment from the heart of Europe to the Russian border.

“Rail Baltica will be the backbone of Nato transportation,” Priit Pruul, head of communications for the project, told The Telegraph after a tour of the construction site in Tallinn. 

“It could cut the transport time for military machinery and equipment from a week to 24 hours… without it, the logistics would be way harder, way more complex.”