The hours-long bombardments across Ukraine came just after a telephone call between the US and Russian presidents ended without any breakthrough.

AFP journalists in Kyiv heard drones buzzing over the capital and explosions ringing out throughout the night as Ukrainian air defence systems fended off the attack.

"We are interested in achieving our goals in the course of the special military operation and it is preferable to do it by political and diplomatic means," Kremlin spokesman Dmitry Peskov told reporters, referring to its invasion, launched in February 2022.

"But as long as that is not possible, we are continuing the special operation," he said in a briefing, including with AFP.

US President Donald Trump had said he made no progress in discussions one day earlier with President Vladimir Putin on ending the war, while the Kremlin vowed to pursue its war aims.

A senior Ukrainian official told AFP that Trump and Ukrainian leader Volodymyr Zelensky were planning to speak later on Friday.

Tymur, a Kyiv resident who said he had experienced previous Russian attacks, told AFP that the assault in the early hours of Friday was different.

"Nothing like this attack had ever happened before. There have never been so many explosions," he said.

- 'War and terror' -

Zelensky said air alerts had begun echoing out across the country as the Trump-Putin call was getting underway.

"Yet again, Russia is showing it has no intention of ending the war and terror," Zelensky said on social media.

"All of this is clear evidence that without truly large-scale pressure, Russia will not change its dumb, destructive behaviour."

He urged the United States in particular to increase pressure on Moscow, which on Friday announced fresh territorial gains on the front line with the capture of a village in the Donetsk region.

Poland said its embassy building in Kyiv had been damaged in the attack but that staff were unharmed.

Germany's foreign ministry meanwhile said that the timing of the attack -- just after the leaders' call -- showed that Moscow "continues to rely on brute force".

"Ukraine needs more to defend itself, not less," the ministry said on social media.

A government spokesman said Germany was exploring the possibility of purchasing more Patriot air defence systems from the United States for Ukraine.

Zelensky said 23 people were wounded in the barrage, which the air force said comprised 539 drones and 11 missiles.

A representative of Ukraine's air force told Ukrainian media that the attack was the largest of the Russian invasion, launched in February 2022.

- 'Complete disregard' -

Overnight Russia attacks have escalated over recent weeks.

An AFP tally found Moscow launched a record number of drones and missiles at Ukraine in June, when direct peace talks between Kyiv and Moscow appeared to stall.

In Kyiv, AFP journalists saw dozens of residents of the capital taking shelter in a metro station.

Yuliia Golovnina, who said she shelters at the metro regularly, described to AFP the worry that comes with hearing an explosion during an attack.

"Will there be another one? Will something collapse on you?" the 47-year-old said.

"So in those seconds, you just hold your breath and wait to see what happens next," she added.

In Kyiv, concerns mount over whether the US will continue delivering military aid, which is key to Ukraine's ability to fend off the drone and missile barrages.

The US announced this week it was reducing some of its aid deliveries.

European Commission President Ursula von der Leyen said this was a clear signal that the 27-nation European Union needed to "step up".

Ukraine has also ramped up its retaliatory strikes in Russia, where a woman was killed when a Ukrainian drone crashed into an apartment building, the acting regional governor in Rostov said.

Talks, spearheaded by the United States to secure a ceasefire, have stalled but Ukraine and Russia announced a fresh swap of prisoners of war with Ukraine.

The two sides said it was part of agreements reached during talks in Istanbul last month.