A fresh wave of Russian missile and drone strikes overnight left more than 20 people dead and scores wounded across Ukraine just hours after US President Donald Trump told Vladimir Putin he had 10-12 days to stop the attacks or face stiff sanctions and tariffs.

Russia has scaled down its Navy Day celebrations due to security concerns from ongoing Ukrainian drone attacks

During the night, Ukrainian forces carried out a major drone attack on Russia's Rostov region, during which the railway infrastructure in the city of Salsk was hit, local Russian officials confirmed.

Polish and allied NATO aircraft were scrambled in response to a large Russian drone and missile attack launched into Ukraine on Sunday night, the Polish military's Operational Command said in a statement.

Military production and defense spending are propping up Russia's economy and may shape its future long after the war in Ukraine.