KYIV, FEBRUARY 12

Russia launched a barrage of ballistic missiles and drones at Ukrainian cities in overnight attacks, officials reported on Thursday as Ukrainian President Volodymyr Zelenskyy said Moscow was "hesitating" about another round of U.S.-brokered talks on stopping the fighting.

Washington has proposed further negotiations next week between Russian and Ukrainian delegations either in Miami or Abu Dhabi, in the United Arab Emirates, which was the location of the last meeting, Zelenskyy said late Wednesday.

Ukraine "immediately confirmed" it would attend, he said. "So far, as I understand it, Russia is hesitating," Zelenskyy told reporters in a messaging app interview late Wednesday.

Kremlin spokesman Dmitry Peskov said on Thursday that another round of talks was expected "soon" but gave no further details.

American officials made no comment on the possibility of further talks as part of a yearlong peace effort by the Trump administration. Zelenskyy said last week that the United States has given Ukraine and Russia a June deadline to reach a deal.

But with Russia's invasion of its neighbor marking its fourth anniversary later this month, disagreements between Moscow and Kyiv over key issues have held up a comprehensive settlement. The issues include who keeps the Ukrainian land that Russia's army has so far occupied, especially in the eastern Donbas industrial heartland, and Moscow's demands for Kyiv to surrender more territory.

Ukraine wants Western-backed security guarantees, including a date for joining the European Union, and a postwar reconstruction package in place before it can contemplate signing a proposed 20-point settlement, Zelenskyy said.

Russia hammers civilian areas

Russia has meanwhile continued to pound Ukrainian civilian areas, including residential areas and the power grid, and Moscow has not responded to a U.S. proposal for an "energy ceasefire" that would also halt Ukrainian drone strikes on Russian oil facilities, Zelenskyy said.

The United Nations High Commissioner for Human Rights, Volker Türk, urged Russia to stop hitting electricity infrastructure, reminding Moscow in a statement that targeting civilian infrastructure is prohibited under international humanitarian law.

Overnight from Wednesday to Thursday, Russia fired 219 long-range strike drones, 24 ballistic missiles and a guided aircraft missile at Ukraine, according to the Ukrainian air force.

The main targets were the Ukrainian capital, Kyiv, the second-largest city of Kharkiv, Dnipro in central Ukraine, and the southern port city of Odesa, the air force said - all cities that have come under relentless bombardment.

In Dnipro, Russian strikes injured four people, including a 4-year-old girl and a newborn boy, regional head Oleksandr Hanzha wrote on Telegram.

In Kyiv, several residential buildings were damaged, and two people were injured, according to the city administration.

In Odesa, one person was injured as a residential high-rise was partially destroyed and a market and a supermarket caught fire, regional head Oleksandr Hanzha wrote on Telegram.

Temperatures have moved above freezing point in Kyiv, but it is still bitterly cold in the city.

Oleksii Kuleba, deputy prime minister for the restoration of Ukraine, said 2,600 buildings were left without heating after the Kyiv attack in addition to 1,100 buildings in the capital that already were without heating due to previous attacks.

In Odesa, nearly 300,000 residents were left without running water, Kuleba said, while in Dnipro the central heating system stopped working for some 10,000 people.

Ukrainian drone flies farthest yet

Ukraine has hit back at Russia with long-range strikes on military targets and oil refineries that generate a large slice of Russia's income.

Ukraine's military general staff said Thursday that one of its domestically developed long-range drones hit the Ukhta oil refinery in Russia's Komi region, around 1,750 kilometers (1,000 miles) from the Ukrainian border.

An official with Ukraine's Security Service, known as the SBU, told The Associated Press that it was the first time Ukrainian drones have flown so far. The official spoke on condition of anonymity because they were not authorized to speak publicly.

Ukraine's general staff also said that one of its domestically produced, long-range "Flamingo" missiles hit one of the Russian military's biggest storage sites for missiles, ammunition and explosives in the Volgograd region and caused major explosions.

Separately, Ukrainian forces also hit and started a fire at the Michurinsk Progress Plant in Russia's Tambov region, a defense enterprise producing high-technology equipment for aviation and missile systems, the General Staff said.

Ukraine's military also confirmed it damaged the Volgograd oil refinery in a strike the previous day.

In other developments:

The White House announced Thursday that first lady Melania Trump helped to reunite a small group of Russian and Ukrainian children with their families after they became separated by the invasion.

Five children - four boys and one girl, from 4 to 15 years old - were reunited with their families in Ukraine, while one child returned to its family in Russia, according to Maria Lvova-Belova, the Kremlin's commissioner for children's rights.

Lvova-Belova is sought for war crimes by the International Criminal Court for allegedly deporting children from Ukraine.

It was the third such family reunification involving the first lady.