Russian, Ukrainian and US officials began a second day of peace talks in Abu Dhabi on Wednesday, resuming meetings which Kyiv and Washington ​depicted on Monday as constructive but produced no early signs of a breakthrough.

Ukrainian and Russian negotiators gave no details after Monday's US-brokered talks, the ‌first between the two warring sides since February, and Moscow and Kyiv went into the talks far apart on terms for a possible settlement.

"We are starting the second day of the talks," Rustem Umerov, Ukraine's top negotiator, said on the Telegram app. "First, there will be a trilateral format with the United States and Russia. After that, we will have a separate meeting with the ​European partners."

Ukrainian President Volodymyr Zelenskiy, who like Russian President Vladimir Putin is not attending the talks, said Monday's "substantive" discussions had covered humanitarian and security issues, ​and that a potential summit of Russian, Ukrainian and US leaders could be discussed on Tuesday.

US Secretary of State Marco Rubio ⁠described the first day of talks as very productive, without giving details. The second day of talks is the last day when meetings are scheduled.

Despite public optimism from ​US President Donald Trump, there has been no sign of major compromises or that new issues are being discussed more than 4-1/2 years after Russia's full-scale invasion of ​Ukraine.

Russian forces control about a fifth of Ukraine, but territory is not the only issue at stake. Others include future security guarantees, which both sides want, and Moscow's demands that Ukraine adopt neutral status and not join NATO.

Each said side the other had launched attacks overnight, despite the peace talks being under way.

Russia struck six large electricity substations in Ukraine's four central regions, Ukrainian Prime Minister ​Sergii Koretskyi said. Ukrainian energy company Naftogaz said Russian jet drones had hit one of its facilities in the eastern Dnipropetrovsk region, causing a fire and damaging equuipment.

Drone debris ​killed two people after hitting an apartment building in Russia's Smolensk region bordering Belarus, the TASS news agency said, citing the regional governor.

Russia's defence ministry said its forces had struck a ‌cargo vessel ⁠in the Black Sea southwest of the Ukrainian port city of Odesa that was carrying weapons and military equipment for Ukraine's armed forces.

Reuters could not verify the reports.

New Attacks

Trump has intensified pressure on Kyiv to reach a deal, saying it is time for Ukraine to end the war or face "a very bad thing". Last week he said the war was close to being settled in a "big beautiful agreement", but he has frequently predicted breakthroughs that have not materialised.

The new American drive for a deal has galvanized ​European officials into pushing for a place ​at the negotiating table to seek ⁠an end to Europe's deadliest conflict since World War Two.

Russian Foreign Minister Sergei Lavrov on Tuesday underlined Moscow's preference for negotiating a broad European security framework before tackling the specifics of the war.

European Commission President Ursula von der Leyen said wider security ​talks should only come after a ceasefire. Lavrov rejected the notion of a truce, saying the Europeans were trying to ​secure breathing space for ⁠Ukraine.

The Kremlin said on Wednesday the Russian delegation in Abu Dhabi had not been in contact with European representatives there, and that no such contacts were planned.

In a call with reporters, Kremlin spokesman Dmitry Peskov also said that Russian President Vladimir Putin is being briefed constantly by the Russian delegation about the talks.

There has been no sign publicly that Putin is ⁠willing to ​drop his demand that Ukraine surrender the entire eastern region of Donbas before a peace deal can ​be struck.

Zelenskiy has repeatedly refused to hand over land that Ukrainian troops have died defending.

Russian advances at the front line have slowed this year, but Moscow has been pounding Ukrainian cities and energy sites, ​while Ukraine has stepped up attacks on Russian oil refineries and other infrastructure.