KYIV — Russia carried out fresh drone attacks on Ukraine's capital Kyiv and the port city of Odesa on Tuesday, killing three people and hitting a maternity hospital, Ukrainian officials said.

Moscow has escalated its attacks on Ukraine, which has hit back with strikes deep inside Russian territory, as peace talks held in Turkiye failed to yield a breakthrough toward ending the three-year conflict.

The overnight strikes on Ukraine followed Russia's biggest drone assault of the conflict on Monday and were part of intensified bombardments — what Moscow says is retaliation for attacks by Ukrainian forces on Russia.

Loud explosions shook Kyiv, and blasts and fires lit up the sky in the early hours of Tuesday morning, leaving palls of heavy smoke over the city, Reuters witnesses said.

In central Kyiv, an AFP journalist heard at least a dozen explosions, anti-aircraft fire and the buzzing of drones.

City officials said one woman was killed and four people were wounded.

After the barrage of more than 300 drones and seven missiles, Ukrainian President Volodymyr Zelensky urged Kyiv's Western allies to respond with "concrete action".

Two people were killed in the Russian strikes on residential buildings in Odesa on Tuesday and at least nine others were wounded, said Governor Oleg Kiper.

"The enemy massively attacked Odesa with strike drones," Kiper wrote on Telegram.

"The Russians hit a maternity hospital, an emergency medical ward and residential buildings."

Moscow has intensified attacks on Ukraine following Kyiv's strikes on strategic bombers at air bases inside Russia on June 1. Moscow also blamed Kyiv for bridge explosions on the same day that killed seven and injured scores.

Russia launched a record 479 explosive drones at Ukraine overnight into Monday morning, the Ukrainian Air Force said.

Kyiv has responded with attacks on Russian territory, targeting transport and weapons production infrastructure.

Russia's transport agency Rosaviatsia said on Tuesday that flight operations were temporarily restricted at more than a dozen Russian airports — a standard procedure during Ukrainian drone attacks.

Flights in Moscow and some other cities were later restored but restrictions were still in place in St. Petersburg as of 0430 GMT. No damage was reported.

Russia's Defense Ministry said it had intercepted 102 Ukrainian drones overnight.

Meanwhile, the Kremlin said on Tuesday that Russia has been ready to start handing over the corpses of Ukrainian soldiers for several days with refrigerated trucks containing the first bodies parked near the border.

Moscow remained ready to return the bodies and was in talks with Kyiv on the subject, but did not yet know exactly how many bodies of Russian soldiers Ukraine was ready to hand over, Kremlin spokesman Dmitry Peskov said.

Agencies via Xinhua