Nato members are sending troops, artillery, and air defense systems to secure its eastern flank after what Poland called an unprecedented Russian drone incursion into its airspace.
In the early hours of Wednesday, three Russian drones were shot down after crossing into Polish airspace.
Other drones crashed to the ground and were later found across eastern Poland.
Poland has requested a UN Security Council session about the incident, which will take place on Friday at 19:00 GMT.
In response to the drone incursion, the Netherlands and the Czech Republic said they would send defences to Poland, while Lithuania would receive a German brigade and greater warning of Russian attacks on Ukraine that could cross over.
Addressing parliament on Thursday, Polish Defence Minister Wladyslaw Kosiniak-Kamysz listed the offers of support from Poland's partners, saying the Dutch were going to deploy air defence systems, artillery and 300 troops, while the Czech would send helicopters and 100 soldiers.
He also said the French and the British could deploy aircraft to secure Nato's eastern flank.
Although Russian drones and missiles have trespassed into some Nato member countries before, this was the most serious incident of its kind since Moscow launched its full-scale invasion of Ukraine in February 2022.
The Kremlin said it had no further comment to make on claims that Russia had deliberately sought to stoke tensions in Poland.
Yet many Polish and European leaders believe the incursion was deliberate.
On Thursday, Nato's top military commander Alexus Grynkewich acknowledged it was not yet known whether the act had been intentional and said even the precise number of drones which had crossed into Polish airspace was still to be determined.
Warsaw will set restrictions for drones and small air traffic along its eastern borders with Belarus and Ukraine, and Latvia has announced its eastern airspace would be closed for a week.
Ukraine's President Volodymyr Zelensky offered guidance and training to Western military representatives on how to fend off Russian aerial attacks as Ukrainian defence forces do on a near-nightly basis.
Add to this the anxiety felt in some quarters of eastern Europe are major joint military exercises between Belarus and Russia, dubbed Zapad 2025, due to start on Friday. Poland said it would close its border with Belarus on Thursday for national security reasons.
