Ukraine on Wednesday called on its Western allies not to fuel tensions inside the country, after a string of embassies in Kyiv announced they would close, citing the threat of a "massive air attack" on the capital.

The warnings of fresh strikes come as Moscow looks to retaliate against Ukraine for firing US-supplied long-range missiles at Russian territory for the first time and with the Kremlin accusing outgoing US President Joe Biden of dragging out the war.

Russia has already ramped up a wave of deadly missile strikes in recent days, targeting residential areas and Ukraine's energy grid. Air alerts blare out across the country daily.

The United States led the wave of closures, saying it was shutting its Kyiv office to the public after having received "specific information of a potential significant air attack" on Wednesday.

It did not provide further details.

Greece, Hungary, Italy and Spain – all Nato members – followed suit, announcing the closures of their diplomatic premises in the capital.

Ukrainian officials criticised the rare move and called on its allies not to spread yet more fear among Ukrainian society.

Kyiv said the "information" the US was referring to looked to be a "psychological operation" launched by Moscow in a bid to destabilise the country.

"We remind you that the threat of strikes by the aggressor state has unfortunately been a daily reality for Ukrainians for over 1,000 days," Ukraine's foreign ministry said in a statement on social media.

Nerves are already frayed in Kyiv after almost three years of war, and Donald Trump's victory in the US presidential election has injected fresh uncertainty.

The Republican has repeatedly criticised US support for Ukraine and claimed he could broker 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.

Both Ukraine and Russia are jockeying for the upper hand on the battlefield before he re-enters the White House in January. (AFP)