Russia's investigators on Thursday said its probe into the 2010 crash of Polish presidential jet is almost complete, rejecting claims that Russian air traffic controllers were to blame.

"The Russian investigation sees no grounds to talk of even minimal responsibility of the flight control group for the air crash," a statement by the Investigative Committee said.

At least nine people lost their lives as a powerful storm barreled through central Europe, causing traffic chaos and leaving thousands without electricity, the authorities said Wednesday.

Seven people perished on Tuesday in Germany, where Storm Niklas strengthened into a hurricane in some areas, packing winds of more than 190 kilometers (120 miles) an hour.

Russia has stepped up military activity to pressure EU leaders who are set to consider fresh sanctions against Moscow, Polish Prime Minister Ewa Kopacz said Tuesday.

Russian President Vladimir Putin ordered massive military maneuvers on Monday, including the deployment of nearly 40,000 troops in the Arctic.

A U.S. Patriot missile battery will take part in a joint exercise this month with Poland designed to reassure NATO allies anxious over a resurgent Russia, the Pentagon said Friday.

The Patriot systems, used to take out incoming missiles, will be deployed for the drill along with 100 U.S. soldiers and about 30 vehicles, spokesman Colonel Steven Warren said.

Poland is seeking advanced cruise missiles to equip three new submarines it wants to acquire by 2030, the NATO member's minister of defense said Thursday.

Tomasz Siemoniak confirmed on Polish public radio that Poland had asked the United States about the availability of Raytheon's Tomahawk cruise missiles.

Polish and Latvian officials on Tuesday voiced skepticism over calls for a European Union army to counter a militarily resurgent Russia.

"It's a very risky idea," Polish Foreign Minister Grzegorz Schetyna told Poland's private Radio Zet in reaction to Sunday's proposal by European Commission head Jean-Claude Juncker.

Poland on Tuesday criticized a Swiss company's sale of high-tech camouflage netting to Russia despite Western sanctions over its role in the Ukraine conflict.

"It must be condemned... supplying this kind of equipment facilitates the aggression of the Russian military," Foreign Minister Grzegorz Schetyna told PAP news agency of the 85 million euros ($91 million sale).

NATO member Poland will train Ukrainian military instructors as it has better facilities than those of its non-allied eastern neighbor, a Polish government spokesperson said Friday.

The announcement came on the heels of a meeting Friday in Warsaw between Polish Prime Minister Ewa Kopacz and Ukrainian National Security and Defense Council chief Oleksandr Turchynov.

Poland's Senate speaker Bogdan Borusewicz said Monday that Russia had denied him entry for the funeral of outspoken opposition activist Boris Nemtsov, who was gunned down in central Moscow on Friday.

"I wanted to pay respect to the slain Boris Nemtsov and to all Russians who think like him. But I have just learned Russian authorities will not allow me to attend the funeral in Moscow," said Borusewicz, a key communist-era dissident and founding member of Poland's anti-regime Solidarity movement.

Looking east to the bloody conflict gripping Ukraine, NATO-member Poland has kicked off an unprecedented military spending spree worth billions to overhaul its forces as Warsaw believes peace in Europe is no longer a given.

The escalation of tensions with Russia over its annexation of Ukraine's Crimean peninsula and subsequent role in the crisis in that country's east has sounded the alarm on NATO's eastern flank in countries that were under Moscow's thumb during the Cold War.