The Russian foreign ministry has called for the expulsion of 35 US diplomats in response to a similar move by Washington.

Foreign Minister Sergei Lavrov said the request had been made to President Vladimir Putin.

The Obama administration expelled 35 Russia diplomats and their families over alleged Russian hacking during the US election campaign.

Russia denies any involvement and calls the US action "ungrounded".

Russian Prime Minister Dmitry Medvedev accused the outgoing administration of President Barack Obama of ending in "anti-Russian death throes".

Diplomatic spat goes undiplomatic

Under the US action taken on Thursday:

• Thirty-five diplomats from Russia's Washington embassy and its consulate in San Francisco were declared "persona non grata" and given 72 hours to leave the US with their families
• Two compounds said to have been used by Russian intelligence services in New York and Maryland will be closed
• Sanctions were announced against nine entities and individuals including two Russian intelligence agencies, the GRU and the FSB

Mr Obama, who will be replaced by Donald Trump on 20 January, had vowed action against Russia amid US accusations that it directed cyber-attacks on the Democratic Party and Hillary Clinton's campaign.

Emails stolen from her campaign manager and from the servers of the Democratic National Committee - some containing embarrassing information for Democrats - were released during the election campaign through the Wikileaks website.

"Of course, we cannot leave attacks like this unanswered," said Mr Lavrov. "Mutuality is the law of diplomacy in international relations."

The foreign ministry suggested expelling 31 US diplomats from Moscow and four from St Petersburg, he said.

It also suggested banning US diplomats from their dachas in Serebryany Bor near Moscow and a warehouse on Moscow's Dorozhnaya Street.

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Tit-for-tat in the Cold War tradition: Analysis by Steve Rosenberg, BBC News, Moscow

Moscow has made it clear it will hit back. The Kremlin has promised an "appropriate response" to the US sanctions; the Russian foreign ministry says there will be Russian "counter-measures".

In the tradition of the Cold War, tit-for-tat is the likely reaction. That would mean Russia expelling a similar number of American diplomats.

But Moscow knows that in three weeks' time President Obama will be vacating the White House. America's new president, Donald Trump, has called for better relations with Moscow.

He has nominated people for senior positions in his administration who are seen as friendly towards Moscow. Rex Tillerson, his nominee for secretary of state, once received an award from President Putin himself.

Will that soften Moscow's response? Or will Russia hit back just as hard?

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Russian foreign ministry spokeswoman Maria Zakharova has denied a report by CNN that Moscow is shutting down a school attended by diplomats' children.

She said it was a "lie" that the Anglo-American School faced closure as retaliation.

Separately, the Russian embassy to the UK tweeted a visual gag calling the Obama presidency a lame duck.

Russian media say the Russians facing expulsion from the embassy in Washington are struggling to buy plane tickets because flights are full ahead of the New Year holiday.

They will be forced to travel to New York, where their chances of finding plane seats are better, an "informed source" told Interfax news agency.

'Getting nasty'

Pavel Felgenhauer, a Russian military affairs analyst, told BBC World Service things were going to get "very nasty" from here on in.

But US Democrat Senator Amy Klobuchar, who is currently on a visit to the Baltic states, told the BBC it would have been a mistake for the US not to respond to the hacking.

"This is something that is not just about American democracy, it's about all democracies," she said. "There's upcoming elections in Germany and France and for the US just to roll over and to let this happen with no response would have been a huge mistake."

President-elect Trump has dismissed the hacking claims as "ridiculous" and said Americans should "get on with our lives" when asked previously about the possibility of sanctions.

US intelligence agencies, including the FBI and CIA, concluded that the aim of the hack was to cause damage to Mrs Clinton and the Democrats and favour Mr Trump.