NATO opened a counter-espionage hub in Poland on Thursday aimed at expanding the alliance's intelligence-gathering capabilities amid tensions with Russia, a senior Polish official said.

The new facility in the southern city of Krakow is focused on "developing the basic norms, principles and activities" for the spy agencies of NATO allies, Defence Minister Antoni Macierewicz said during opening ceremonies at the venue attended by his Hungarian, Romanian and Slovak counterparts.

Espionage now "covers all areas of life", affecting the military and critical civilian infrastructure via both cyber-tools and conventional spying, Macierewicz added, quoted by the Polish PAP news agency.

NATO's Counter Intelligence Centre of Excellence was formally endorsed in 2015 at talks in the alliance's Allied Command Transformation facility in Norfolk, Virginia.

The new venue comes as NATO's relations with Russia have hit their lowest point since the Cold War over the conflict in Ukraine, leading to a spike in spying claims.

The US-led alliance has also bolstered its forces in eastern Europe with four international battalions acting as tripwires against possible Russian adventurism in the region.

Separately, the US Army set up a new European headquarters in Poland in May to command some 6,000 of its troops deployed in NATO and Pentagon operations across the alliance's eastern flank since the beginning of the year.

NATO already has 21 other Centres of Excellence dotted across its 28 members for a wide range of activities from cyber defence and military medicine to counter-terrorism.