Russia is "ready in principle" to resume talks with the US and Ukraine on ending the conflict, Vladimir Putin's top aide has said.

Yuri Ushakov was speaking after Putin met US President Donald Trump's special envoy Steve Witkoff in the Russian city of St Petersburg.

Ukraine's President Volodymyr Zelensky and his European allies have been pressing Moscow for an immediate resumption of the talks suspended in February, and Ushakov said a new round could be held next month.

Russia has for months refused talks as it believes it is winning on the battlefield with Ukraine facing an acute shortage of interceptors against deadly Russian missile attacks.

Witkoff went to St Petersburg after meeting Zelensky as well as the leaders of Norway and Finland in the Norwegian capital, Oslo, on Monday.

It is not clear what specific proposals Witkoff brought to Putin, but Zelensky said after talks in Oslo that "strong" security guarantees for Ukraine and energy ceasefire proposals had been discussed.

Ushakov said their ideas were not very "useful".

Top officials from Russia, Ukraine and the US have held several rounds of talks aimed at ending the war that began in February 2022 when Putin launched a full-scale invasion of Ukraine.

Russia blamed last month's "massive" Ukrainian strikes during its general elections for their disruption.

Speaking to reporters after Wednesday's talks in St Petersburg, Ushakov suggested that a new round could be held around 10 November in Abu Dhabi, the capital of the United Arab Emirates.

He stressed that the talks must focus on "building a security system for Russia and Ukraine after the end of the conflict."

A US official later told the BBC that Witkoff and Trump's son-in-law Jared Kushner, another key negotiator, had proposed at Tuesday's talks in the Norwegian capital "a trilateral meeting at the technical level between the US, Russia, and Ukraine".

"This was accepted by the Ukrainians in Oslo yesterday and by the Russians in St Petersburg today," said the official, who spoke on condition of anonymity.

Ushakov also told reporters that President Putin reiterated to Witkoff that Russian troops were advancing everywhere across the vast front line and had a "strategic initiative".

Ukraine and its European allies are disputing Putin's claim, pointing to a virtual stalemate on the front.

The talks in Oslo and St Petersburg - which Witkoff described as "constructive" - were held amid a growing row between Ukraine and the US.

Trump has said it is time for Ukraine to get a new president, and most recently "for somebody else to negotiate on behalf of Ukraine".

Trump has blamed Ukraine's attacks on Russian oil refineries for fuel prices which have been rising since the start of the US-led war on Iran.

He was heavily criticised by Democratic and some Republican lawmakers after lifting sanctions on Russia - allowing it to release tonnes of diesel "to the American and global marketplace".

That was despite signing legislation to authorise fresh US sanctions and tariffs on nations that import Russian oil and gas just weeks earlier.

Zelensky - and Ukraine's European allies - criticised Trump's move.

Last week, Kyiv accused Washington of withholding critical intelligence to warn Ukrainians about incoming Russian ballistic missile launches, resulting in many civilian deaths. US Secretary of State Marco Rubio on Tuesday rejected such accusations as "scandalous", and Zelensky said after the Oslo talks that intelligence sharing "works now".

Ukraine's military has also complained of speed restrictions by the US satellite internet network Starlink which is owned by Elon Musk which constricted its ability to use drones to conduct strikes against Russia.

US officials have denied having requested such a slowdown and a bipartisan group of US senators has called for an urgent investigation.

Before the Putin-Witkoff talks started, Russia released Stephen Hubbard, a 74-year-old American citizen who was jailed for nearly seven years for allegedly fighting on behalf of Ukraine.

Trump said the former teacher was "on his way back home" and "there was no 'swap' necessary", while Witkoff called Putin a "humanitarian" for agreeing the release.

When asked by a BBC reporter whether he agreed with such description of the Kremlin leader, US Vice-President JD Vance said: "I agree with Steve Witkoff saying something nice to a person who just released an American hostage.

"Whether you agree with the underlying sentiment or not, Steve Witkoff is a diplomat. His job is to go over there and get a job done. I care much less about what Steve said and about the fact that he is bringing an American hostage home to his family."