Talks between envoys from Ukraine, Russia and the United States in recent days in Abu Dhabi were constructive and another round is planned for next week, spokesman Dmitry Peskov told journalists.
He reported no major breakthrough so far, however, and added: "The very fact that these contacts have begun in a constructive way can be assessed positively but there is still serious work ahead".
Officials revealed few details of the talks held on Friday and Saturday, which were part of a yearlong effort by US President Donald Trump's administration to steer the sides toward a peace deal and end almost four years of all-out war.
While Ukrainian and Russian officials have agreed in principle with US calls for a compromise, the two sides differ deeply over what an agreement should look like.
Meanwhile, the grinding war of attrition along the roughly 1000km front line snaking through eastern and southern Ukraine has dragged on, and Ukrainian civilians are enduring another winter of hardship after Russian bombardment of cities in the rear.
Ukrainian President Volodymyr Zelenskiy also described the Abu Dhabi talks as constructive, although he noted that "complex political issues ... remain unresolved".
A new round of trilateral meetings is expected later this week, Zelenskiy said, without giving a date.
Negotiators will return to the United Arab Emirates on Sunday for more talks, according to a US official, speaking on condition of anonymity because they were not authorised to speak to the media.
The weekend talks covered a broad range of military and economic matters and included the possibility of a ceasefire before a comprehensive deal, the official said.
Zelenskiy said on Sunday that a document setting out US security guarantees for Ukraine in a postwar scenario is "100 per cent ready," although it still needs to be formally signed.
Kyiv has insisted on postwar US security commitments as part of any broader peace agreement with Russia after its 2014 annexation of Crimea and support for separatist rebels in eastern Ukraine, followed by its full-scale invasion in February 2022.
Zelenskiy has acknowledged that there are fundamental differences between Ukrainian and Russian positions although he said last week that peace proposals are "nearly ready".
A central issue is whether Russia should keep or withdraw from areas of Ukraine its forces have occupied, especially Ukraine's eastern industrial heartland called the Donbas, and whether it should get land there that it has not yet captured.
German Foreign Minister Johann Wadephul on Monday chided Russia for its "stubborn insistence on the decisive territorial issue".
He said during a visit to Latvia that "if there is no agility here, I am afraid that the negotiations may take a long time or will not be successful now".
Russia's defence ministry said on Monday that air defences downed 40 Ukrainian drones late on Sunday and early on Monday, including 34 over the Krasnodar region and four over the Sea of Azov.
Krasnodar officials said drone fragments fell on two industrial plants in the city of Slavyansk, sparking fires that were extinguished.
One person was injured, they said.
Ukraine's general staff said an oil refinery in Russia's Krasnodar region was targeted by Ukrainian forces.
The facility supplied the Russian military, it added.
Russian forces launched 138 drones at Ukraine overnight, 110 of which were shot down or suppressed, Ukraine's air force said, and 21 of them hit targets in 11 locations.
