Russia fired hundreds of drones, artillery and a ballistic missile at Ukraine between late Tuesday and early Wednesday, defying calls by US President Donald Trump to reach a peace deal.

Trump on Monday threatened to impose severe sanctions against Moscow unless it reached a peace settlement within 50 days to end its three-year war on Ukraine.

According to regional authorities, Russia dropped a 500-kilogramme (1,100 pound) bomb on Dobropillia, which is just 20 kilometres (12 miles) from the frontline.

"Updated information on the shelling of Dobropillia...1 person killed and 21 wounded," Vadym Filashkin from the Donestk reional administration said on social media. He added that the rush hour attack hit 54 shops and 13 buildings around the crowded square.

"It is likely that people are still trapped under the rubble, and the search for survivors continues."

Ukrainian and Russian officials last met for direct peace talks more than a month ago, and no further meetings have been scheduled despite the Kremlin saying it is open to contacts.

Russia fired at least 400 drones at Ukraine between late Tuesday and early Wednesday, as well as an Iskander ballistic missile launched from the annexed Crimean peninsula, the Ukrainian air force said.

The attacks killed one and left dozens injured on top of the Dobropillia toll, according to Ukrainian authorities.

Russia has stepped up its summer campaign against Ukraine in recent weeks as Washington-mediated ceasefire talks stall.

Its army has pushed ahead on the battlefield, while pounding Ukraine with drone, artillery and missile strikes.

Trump said Monday he had struck a deal with NATO to supply more US air defence systems and weapons to Ukraine, citing his frustration with Russia's refusal to accept a ceasefire.