BERLIN — Poland Prime Minister Donald Tusk warned that Russia is planning strikes on countries supporting Ukraine.
Addressing Polish lawmakers on Thursday, Tusk said Russia intends to send drones or missiles into NATO territory and then claim that these incidents are "accidental."
His warning followed a series of incidents blamed on Russia along NATO's eastern flank.
Tusk said that these potential strikes "intend to paralyze NATO" or "at least weaken the alliance's willingness to respond collectively" in an attempt to demonstrate that Article 5 "exists only in theory."
NATO's Article 5 states that an armed attack against one member is considered an attack against all members.
Tusk said he'd received intelligence from NATO, Ukraine and U.S. agencies but did not specify which ones he was citing.
He stressed that "there is nothing to suggest an invasion" but warned that Poland is about to face a real test as one of Ukraine's staunchest allies.
Tusk, who was addressing the Polish parliament on the 87th anniversary of the Soviet invasion of Poland in 1939, also warned that political shifts within Europe are undermining NATO's commitment to Ukraine.
He appeared to refer to Russia-friendly political parties currently gaining ground in Europe, such as Marine Le Pen's National Rally in France and the far-right Alternative for Germany. Tusk said that although those parties ostensibly invoke symbols of peace, they are calling for the capitulation of Ukraine.
Tusk also questioned whether NATO members in the west were giving any thought to the alliance's eastern flank, pointing out that Poland is more likely to need allied loyalty under Article 5 than Portugal or Ireland due to its proximity to Russia and Ukraine.
But just after Tusk spoke, President Trump announced progress in establishing a permanent U.S. Army Base in Poland, where troops are currently hosted on a rotational basis.
"If this happens, the location will be announced very soon," Trump said in a social media post. "This will be a historic step for our Great U.S./Polish Alliance."
Tusk's warning comes at the end of a week of airspace violations and incidents that European countries are blaming on Russia.
On Sunday a Russian drone hit a passenger train in Ukraine just over a mile from the Polish border, shortly after former British Prime Minister Boris Johnson and other European security officials had traveled through the area.
On Monday, the Polish military said it retrieved a Russian drone just off the country's northwestern coast, which authorities say was carrying a warhead.
On Tuesday, NATO jets shot down a drone in Lithuania.
European countries are starting to speak up directly about what they perceive to be a coordinated campaign of hybrid attacks on their soil. These incidents include acts of sabotage, cyberattacks or disinformation, but do not reach the bar of an act of war.
Earlier this month, the German government blamed Russian operatives for an attempted drone strike on an airport that serves as a major NATO hub.
Russia's Foreign Ministry denies the accusations, calling them "contrived" and "far-fetched."
But Tusk's warning was as much for NATO as it was for Moscow.
He ended his speech by appealing for unity and a resolute response to any attacks and underscored Poland's own commitment to NATO's defense .
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