Russia on Wednesday accused the U.S. of prolonging the "war in Ukraine" by stepping up weapons deliveries to Kyiv ahead of Donald Trump's return to the White House.

Both Moscow and Kyiv are jockeying to secure an upper hand on the battlefield ahead of Trump assuming office in January 2025.

The Republican has repeatedly criticized U.S. support for Ukraine and claimed he could secure a ceasefire within hours – comments that have triggered fears in Kyiv and Europe about Ukraine's ability to withstand the Russian attacks without American support.

Moscow has significantly escalated its aerial campaign this week, launching multiple deadly missile strikes and targeting Ukraine's energy grid.

Ukraine meanwhile has fired long-range U.S.-supplied ATACMS missiles at Russian territory for the first time since the White House authorised such strikes, drawing scorn and promises of retribution in Moscow.

"If you look at the trends of the outgoing U.S. administration, they are fully committed to continuing the war in Ukraine and are doing everything they can to do so," Kremlin spokesman Dmitry Peskov told reporters.

Peskov was responding to the U.S. saying it would soon provide Ukraine with antipersonnel land mines.

'Laughable, Absurd'

Ukraine's President Volodymyr Zelenskyy told Fox News late on Tuesday that Ukraine would lose if Washington, its main military backer, pulled funding.

Washington has sought commitments from Ukraine to use the freshly pledged mines on its own territory and only in areas that are not populated in order to decrease the risk they pose to civilians.

The mines are known as being "non-persistent" because they go inert after a set period of time, when their battery power runs out.

The United Nations has called Ukraine "the most mined country in the world," almost three years into Russia's full-scale military offensive and more than a decade after Russian-backed militias in the Donbas region launched a bloody campaign to secede from Kyiv.

The U.S. decision to give Ukraine more mines has drawn some criticism from campaign groups.

The International Campaign to Ban Landmines (ICBL) told AFP it "condemns this terrible decision by the US" and said it would be "working to get the U.S. to reverse it."

The Kremlin on Wednesday also rejected as "absurd" and "laughable" suggestions it was involved in the cutting of telecommunications cables running under the Baltic Sea.

Two telecommunications cables cut in the Baltic Sea in 48 hours prompted European officials to say Tuesday that they suspect "sabotage" and "hybrid warfare" linked to Russia's offensive on Ukraine.

"It's quite absurd to keep blaming Russia for everything without any grounds. It is laughable in the context of the lack of any reaction to Ukraine's sabotage activities in the Baltic Sea," Peskov said, accusing Kyiv of blowing up the underwater Nord Stream gas pipelines.

'Cannot Be Defeated'

Amid a wave of aerial attacks this week, the U.S. embassy in Kyiv said it would close on Wednesday, warning it had "received specific information of a potential significant air attack" on the Ukrainian capital.

Russia's forces have also been advancing on the ground.

They claimed Wednesday to have captured the Ukrainian town of Illinka, close to the strategic hub of Kurakhove in the eastern Donetsk region.

In another sign of escalation, President Vladimir Putin on Tuesday signed a decree lowering the threshold for when Russia would use nuclear weapons.

Sergey Naryshkin, director of Russia's foreign intelligence service, said the new nuclear policy "effectively rules out the possibility of beating Russia's armed forces on the battlefield," state media reported Wednesday.

Despite increased rumblings of possible talks to end the conflict, there is no sign of Putin and Zelenskyy being anywhere close to converging on a possible deal.

Zelenskyy has ruled out ceding territory in exchange for peace, while Putin has demanded Ukraine's troops abandon four regions in its south and east as a precondition to peace talks.

Both have said they do not want a temporary ceasefire or freezing of the conflict.