The Russian delegation has already touched down in Abu Dhabi, according to Russian state media, though it was unclear if US and Ukrainian delegates had arrived.
Several rounds of diplomacy between the sides have failed to strike a deal on ending Europe's deadliest conflict since World War II, which began when Russia invaded in February 2022.
A massive Russian drone and missile barrage in the run-up to the talks, pounding Ukraine's energy grid and knocking out power and heating in temperatures far below freezing, threatened to overshadow any chances of progress in the Emirati capital.
"Each such Russian strike confirms that attitudes in Moscow have not changed: they continue to bet on war and the destruction of Ukraine, and they do not take diplomacy seriously," Ukrainian President Volodymyr Zelensky said on Tuesday.
"The work of our negotiating team will be adjusted accordingly," he said, without elaborating.
The main sticking point is the long-term fate of territory in eastern Ukraine.
Moscow is demanding that Kyiv pull its troops out of swathes of the Donbas, including heavily fortified cities atop vast natural resources, as a precondition of any deal.
It also wants international recognition that land seized in the invasion belongs to Russia.
Kyiv has said the conflict should be frozen along the current front line and has rejected a unilateral pull-back of forces.
The talks -- set for Wednesday and Thursday -- were postponed from last weekend due to what the Kremlin called scheduling issues between the three sides.
Ukraine's delegation will be headed by Security Council chief Rustem Umerov, a shrewd negotiator hailed by colleagues as a worker of diplomatic "wonders".
Russia's top negotiator will be its military intelligence director Igor Kostyukov, a career naval officer sanctioned in the West over his role in the Ukraine invasion.
At a previous round of talks in Abu Dhabi last month, the US team was led by President Donald Trump's ubiquitous envoy Steve Witkoff.
Russia, which occupies around 20 percent of its neighbour, has threatened to take the rest of the Donetsk region if talks fail.
Ukraine has warned that ceding ground will embolden Moscow and that it will not sign a deal that fails to deter Russia from invading again.
Kyiv still controls around one-fifth of the Donetsk region.
Russia also claims the Lugansk, Kherson and Zaporizhzhia regions as its own, and holds pockets of territory in at least three other Ukrainian regions in the east.
On the battlefield, Russia has been notching up gains at immense human cost, hoping it can outlast and outgun Kyiv's stretched army.
On Tuesday, a Russian drone strike on the southern Ukrainian city of Zaporizhzhia killed three and wounded at least 11 people, regional governor Ivan Fedorov said on Telegram.
Meanwhile, a 68-year-old man and 38-year-old man were killed in a drone attack on the Dnipropetrovsk region, Mykola Lukashuk, head of the regional administration, said on the messaging platform.
Sergiy Lysak, who leads the Odesa military administration, confirmed more than 20 residential buildings, two kindergartens and one school were damaged in an attack in the southern Ukrainian city overnight. No one was killed but two people were injured.
Hundreds of thousands have been left without heat and power in the Ukrainian capital this year after massive Russian strikes severely damaged Kyiv's energy grid.
Following the first round of US-brokered talks in Abu Dhabi last month, Ukrainians were doubtful any deal could be struck with Moscow.
"I think it's all just a show for the public," Petro, a Kyiv resident, told AFP.
"We must prepare for the worst and hope for the best."
