MOSCOW/KYIV/BRUSSELS/VILNIUS - New sanctions imposed by the United States on Russian oil companies will not significantly impact Russia's economic health, Russian President Vladimir Putin said Thursday.

Putin called the sanctions "an attempt to put pressure on Russia" and "unfriendly", adding that they do not strengthen Russia-US relations.

The US Treasury Department on Wednesday announced sanctions on Russia's two largest oil producers, Rosneft and Lukoil, in a bid to pressure Moscow to agree to an immediate ceasefire in Ukraine.

Commenting on US President Donald Trump's remarks on Wednesday that he had canceled his planned meeting with Putin, the Russian president said Russia has always supported continued dialogue.

He added that it would be a mistake to approach the Russia-US summit without preparation.

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Meanwhile, the Russian Foreign Ministry said the sanctions could stifle efforts to end the conflict with Ukraine.

"We view this step as entirely counterproductive, including in terms of signaling support for achieving meaningful negotiated solutions to the Ukrainian conflict," Russian Foreign Ministry spokesperson Maria Zakharova said.

She warned that the new sanctions could have negative consequences for the US itself and harm global economic stability.

Zakharova added that the measures would not cause serious difficulties for Russia, noting that the country has developed a "strong immunity" to Western restrictions and will continue to strengthen its economy and energy sector.

Ukraine imposes blackouts

Also on Thursday, Ukraine's state-run energy company Ukrenergo imposed rolling power outages nationwide after recent Russian missile and drone strikes on energy infrastructure.

Electricity restrictions will be in place from 7 am to 11 pm in 12 regions, the company said in a statement on Telegram. The measures will affect households, businesses and industrial users.

Parts of the eastern Kharkiv region and the northern Chernihiv region were completely cut off from power as a result of the attacks.

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Overnight Wednesday, Russia launched a large-scale strike on Ukraine's critical infrastructure, firing 405 drones and 28 missiles, according to the Ukrainian Air Force. Air defense units intercepted 333 drones and 16 missiles. 

1,000 bodies received from Russia

Ukraine said Thursday it had received 1,000 bodies from Russia in the ongoing conflict, which Moscow said were believed to be Ukrainian soldiers.

The International Committee of the Red Cross assisted in returning the remains to Ukraine.

Ukrainian forensic experts will conduct examinations to identify the bodies. 

Frozen Russian assets to fund Ukraine aid

Separately, EU leaders failed to agree on a plan to use frozen Russian assets to finance new loans for Ukraine, after divisions resurfaced at a European Council summit.

The summit's conclusions contained significantly softer wording than earlier drafts, reflecting Belgium's objections and legal concerns raised by the European Central Bank (ECB).

EU leaders reaffirmed their political, economic and military support for Ukraine but stopped short of backing any specific funding mechanism. The conclusions merely invited the Commission to present, "as soon as possible, options for financial support based on an assessment of Ukraine's financing needs", saying that the issue would be revisited at the next EU summit in December.

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The dispute centers on a proposal outlined by European Commission President Ursula von der Leyen in her September State of the Union address to create a "reparation loan" of around 140 billion euros ($163 billion), backed by frozen Russian sovereign assets.

The plan is supported by Germany, France and the Baltic States, but opposed by Belgium and the ECB, which warn that it could breach international law and threaten eurozone financial stability.

Russian military airplanes briefly violate Lithuania's airspace

In another development, Lithuania's Armed Forces said a Russian fighter jet and a refueling aircraft briefly violated the country's airspace near the southwestern town of Kybartai, which borders Russia's Kaliningrad exclave.

In response to the incident, two Spanish Air Force Eurofighter Typhoon jets, currently serving under NATO's Baltic Air Policing mission, were scrambled and flew to the area of the violation.

Lithuanian President Gitanas Nauseda and Prime Minister Inga Ruginiene called the alleged violation a serious breach of international law