Russian President Vladimir Putin on Thursday promised a "significant" response to "Europe's militarisation", as he addressed a foreign policy forum in southern Russia.
Relations between Russia and the EU spiralled downward after Moscow sent troops into Ukraine, leading the bloc to bolster its defence.
"We are closely monitoring the rising militarisation of Europe," he told the forum's audience, adding: "Retaliatory measures by Russia will not take long. The response to such threats will be very significant."
"Russia will never show weakness or indecisiveness," Putin added.
Drone incidents in Denmark and aerial incursions from Moscow in Estonia and Poland have heightened fears that Russia's war against Ukraine could spill over Europe's borders.
Putin accused Europe of stoking "hysteria" to excuse rising military spending and said Russia did not pose a threat. "Just calm down," the Russian President said.
He claimed Russia was fighting the NATO alliance in Ukraine and mocked US President Donald Trump's comment that Russia was a "paper tiger."
"But given we are at war with the entire NATO bloc and are advancing, feeling confident, and we are still being called a paper tiger, then what is NATO itself?" Putin said.
The Russian leader also blamed Kyiv for conducting strikes around the occupied Zaporizhzhia nuclear power plant, warning that Moscow may respond in kind.
Europe's largest atomic energy plant -- which is in a cold shutdown mode -- lost power over a week ago, the longest outage so far.
Russia and Ukraine have traded blame for attacking the grid powering the facility.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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