Ukraine crisis: This is Europe’s biggest crisis in the 21st century, warns William Hague as Russia defiantly threatens a military assault on Crimea

Ukraine’s acting president has received strong words of support from the West after the occupation of Crimea

Western countries scrambled to pile the pressure on Russia on Monday in an effort to bring an end to its occupation of Crimea, as Ukraine’s acting president warned of a growing military presence on the troubled peninsula.

It came as the commander of Russia’s Black Sea Fleet Aleksander Vitko, threatened a full assault if Ukrainian forces in Crimea did not surrender by dawn, defence sources in Kiev said. However, Interfax news agency later quoted a Russian spokesman denying that any such ultimatum had been issued.

Last night President Barack Obama accused Russia of being “on the wrong side of history” and said diplomatic and economic steps to isolate Moscow were being assessed.

“Over time this will be a costly proposition for Russia and now’s the time for them to consider whether they can serve their interests in a way that resorts to diplomacy as opposed to force,” he said.

Meanwhile there were reports last night that Russia’s UN envoy said ousted Ukrainian President Viktor Yanukovych had requested Russia to use military force in Ukraine.

Vitaly Churkin said in a speech at the UN that Mr Yanukovych had made the request in writing to Russian President Vladimir Putin.

William Hague, the Foreign Secretary, visited Ukraine’s new government in Kiev yesterday, where he described the deteriorating situation as the “biggest crisis in Europe in the 21st century”. He warned the “world cannot just allow this to happen” and added: “ Russia should be in no doubt about this. This is something that we take very seriously.”

Read more: Ukraine appeals to Moscow: ‘This is a crime and you will answer for it’
Russia dismisses '3am ultimatum' as 'total nonsense
Latest: Ukraine 'on the brink of disaster' as Russian troop movements prompt stand-off
Ukraine crisis: Nato ‘betrayal’ and Brussels rhetoric pushing Vladimir Putin to act
Ukraine crisis: UK ministers to boycott Paralympics in response to Russia’s ‘declaration of war’

Ukraine’s acting President, Olexander Turchynov, said Russia’s Black Sea Fleet had trapped Ukrainian navy vessels in the bays of Sevastopol, the Crimean port where the Russian fleet has a base.

“The situation in Crimea remains tense and Russia’s military presence is growing,” Mr Turchynov said. “I appeal to Russia’s leadership – stop the provocative actions, aggression and piracy. This is a crime and you will answer for it.”

But the Russian Foreign Minister Sergei Lavrov insisted “this is a question of defending our citizens and compatriots, ensuring human rights, especially the right to life”.

David Cameron, the Prime Minister, signalled last night that Russia would face economic sanctions from the EU if it fails to withdraw its troops from Ukrainian soil. He raised the prospect of “ diplomatic, political, economic and other pressure” being brought to bear against Moscow.

But it emerged later that Britain would be unlikely to take any steps that could hit trade with Russia or block Russian involvement in the City of London. According to a private government briefing note that emerged last night, ministers are considering visa restrictions and travel bans on key Russian figures.

The note, which was photographed as an official carried it into Downing Street, said ministers should “discourage any discussion (eg at Nato) of contingency military preparations” and support “ contingency EU work on providing Ukraine with alternative gas” and oil supplies “if Russia cuts them off”. It said “The UK should not support for now trade sanctions or close London’s financial centre to Russians”.

The White House said yesterday it would no longer be sending a presidential delegation to the winter Paralympics in Sochi. It said it and six other nations were suspending preparations for a summit of the Group of 8 that Russia is due to host, also in Sochi, in June.

The US Secretary of State, John Kerry, was flying last night to Kiev while the European Union set up an emergency summit of its leaders in Brussels on Thursday to craft a response to the crisis.

A US official said the country was “moving down the path” of imposing economic sanctions on Russia unless the crisis is defused quickly.

The Washington Post accused President Obama of practising a foreign policy “based on fantasy” rather than realities. “Obama has led a foreign policy based more on how he thinks the world should operate than on reality,” it lamented noting his “failure to enforce his ‘red line’” in Syria was a liability.

British sources said the UK was keen to keep communications open with the Putin administration in the hope of moving towards a “ de-escalation” of the situation. However, London repeatedly warned yesterday that the invasion of Crimea could result in “significant costs” for the Russian government. The warning will be reinforced at a meeting of foreign ministers, including Mr Lavrov, at the UN Security Council tomorrow. Mr Cameron chaired a meeting of the National Security Council in London to discuss the crisis..

Speaking afterwards, he said all nations needed to send a “clear message” to Moscow that its actions could not be tolerated. “What we want to see is a de-escalation rather than a continuation down the path that the Russian government has taken, violating the sovereignty and territorial integrity of another country,” he said. “We shall have to bring to bear diplomatic, political, economic and other pressures in order to make this point.”

Start your day with The Independent, sign up for daily news emails
ebooksAn introduction to the ground rules of British democracy
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Technical Author / Multimedia Writer

Negotiable: Recruitment Genius: This recognized leader in providing software s...

Recruitment Genius: Clinical Lead / RGN

£40000 - £42000 per annum: Recruitment Genius: This is an exciting opportunity...

Recruitment Genius: IT Sales Consultant

£35000 - £40000 per annum: Recruitment Genius: This IT support company has a n...

Recruitment Genius: Works Engineer

Negotiable: Recruitment Genius: A works engineer is required in a progressive ...

Day In a Page

Isis profits from destruction of antiquities by selling relics to dealers - and then blowing up the buildings they come from to conceal the evidence of looting

How Isis profits from destruction of antiquities

Robert Fisk on the terrorist group's manipulation of the market to increase the price of artefacts
Labour leadership: Andy Burnham urges Jeremy Corbyn voters to think again in last-minute plea

'If we lose touch we’ll end up with two decades of the Tories'

In an exclusive interview, Andy Burnham urges Jeremy Corbyn voters to think again in last-minute plea
Tunisia fears its Arab Spring could be reversed as the new regime becomes as intolerant of dissent as its predecessor

The Arab Spring reversed

Tunisian protesters fear that a new law will whitewash corrupt businessmen and officials, but they are finding that the new regime is becoming as intolerant of dissent as its predecessor
King Arthur: Legendary figure was real and lived most of his life in Strathclyde, academic claims

Academic claims King Arthur was real - and reveals where he lived

Dr Andrew Breeze says the legendary figure did exist – but was a general, not a king
Who is Oliver Bonas and how has he captured middle-class hearts?

Who is Oliver Bonas?

It's the first high-street store to pay its staff the living wage, and it saw out the recession in style
Earth has 'lost more than half its trees' since humans first started cutting them down

Axe-wielding Man fells half the world’s trees – leaving us just 422 each

However, the number of trees may be eight times higher than previously thought
60 years of Scalextric: Model cars are now stuffed with as much tech as real ones

60 years of Scalextric

Model cars are now stuffed with as much tech as real ones
Theme parks continue to draw in thrill-seekers despite the risks - so why are we so addicted?

Why are we addicted to theme parks?

Now that Banksy has unveiled his own dystopian version, Christopher Beanland considers the ups and downs of our endless quest for amusement
Tourism in Iran: The country will soon be opening up again after years of isolation

Iran is opening up again to tourists

After years of isolation, Iran is reopening its embassies abroad. Soon, there'll be the chance for the adventurous to holiday there
10 best PS4 games

10 best PS4 games

Can’t wait for the new round of blockbusters due out this autumn? We played through last year’s offering
Transfer window: Ten things we learnt

Ten things we learnt from the transfer window

Record-breaking spending shows FFP restraint no longer applies
Migrant crisis: UN official Philippe Douste-Blazy reveals the harrowing sights he encountered among refugees arriving on Lampedusa

‘Can we really just turn away?’

Dead bodies, men drowning, women miscarrying – a senior UN figure on the horrors he has witnessed among migrants arriving on Lampedusa, and urges politicians not to underestimate our caring nature
Nine of Syria and Iraq's 10 world heritage sites are in danger as Isis ravages centuries of history

Nine of Syria and Iraq's 10 world heritage sites are in danger...

... and not just because of Isis vandalism
Girl on a Plane: An exclusive extract of the novelisation inspired by the 1970 Palestinian fighters hijack

Girl on a Plane

An exclusive extract of the novelisation inspired by the 1970 Palestinian fighters hijack
Why Frederick Forsyth's spying days could spell disaster for today's journalists

Why Frederick Forsyth's spying days could spell disaster for today's journalists

The author of 'The Day of the Jackal' has revealed he spied for MI6 while a foreign correspondent