Russia And China 'In Agreement' Over Ukraine
Russia has said China is largely "in agreement" over Ukraine, after other world powers condemned Moscow for sending troops into the country.
Hundreds of Russian soldiers have surrounded a military base in Crimea, preventing Ukrainian soldiers from going in or out.
The convoy blockading the site, near the Crimean capital Simferopol, includes at least 17 military vehicles.
Russian troops are also reported to have taken control of a ferry terminal in the city of Kerch on the eastern tip of Crimea, which has a majority Russian-speaking population.
Ukraine's defence ministry said two Russian fighter jets violated the country's air space in the Black Sea on Sunday night and that it had scrambled an interceptor aircraft to prevent the "provocative actions".
And reports claimed pro-Russian protesters had occupied a floor of the regional government building in Donetsk. The 11-storey building has been flying the Russian flag for the last three days.
Ukrainian prime minister Arseny Yatseniuk has insisted his country "will never give up Crimea to anyone" and urged Russian forces to withdraw.
Mr Yatseniuk said: "I was and am a supporter of a diplomatic solution to the crisis, as a conflict would destroy the foundations for stability in the whole region."
In an interview with Sky News, Foreign Secretary William Hague said the crisis is likely to take some time to resolve.
He said: "I think we probably are looking at a long period of very active diplomacy and looking for solutions to this since there is no sign of a change in the Russian position on this.
"It's impossible to be optimistic at the moment. We're not in any position to be optimistic about the security situation and what is happening in the Crimea."
The crisis has had a huge knock-on effect on global stock markets, with Moscow's stock exchange plunging as much as 10% on Monday morning .
Russia's central bank raised its rate to 7% from 5.5% as the ruble hit an historic low against the dollar and the euro.
Russian foreign minister Sergei Lavrov discussed Ukraine by telephone with his Chinese counterpart, Wang Yi, on Monday, and claimed they had "broadly coinciding points of view" on the situation there, according to a ministry statement.
Speaking at the UN Human Rights Council in Geneva later, Mr Lavrov said Russian troops were necessary in Ukraine "until the normalisation of the political situation" and dismissed threats of sanctions and boycotts.
He added: "We call for a responsible approach, to put aside geopolitical calculations, and above all to put the interests of the Ukrainian people first."
Chinese foreign ministry spokesman Qin Gang said: "China has always upheld the principles of diplomacy and the fundamental norms of international relations.
Rumours of President Viktor Yanukovych's sprawling 350-acre estate had circulated in Ukraine for years, but it was not until now ordinary citizens could glimpse inside. While the eastern European country's economy struggled, Yanukovych lived in the lap of luxury with gilded furniture, vintage cars and sweeping staircases.
Since the President fled Kiev last week the building has been abandoned to hundreds of Ukrainians who have explored the opulent grounds and house. But instead of ransacking the house, anti-government protesters have calmly taken pictures and fed Yanukovych's collection of exotic birds.
As the tense stand-off continues, the other seven nations of the G8 urged Moscow to hold talks with Kiev.
"We, the leaders of Canada, France, Germany, Italy, Japan, the United Kingdom and the United States and the President of the European Council and President of the European Commission, join together today to condemn the Russian Federation's clear violation of the sovereignty and territorial integrity of Ukraine," they said in a statement.
"We have decided for the time being to suspend our participation in activities associated with the preparation of the scheduled G8 Summit in Sochi in June."
British Foreign Secretary William Hague, who is in Kiev for talks on the crisis , said Russia has taken operational control of Crimea.
He described Russia's intervention in Ukraine as the biggest crisis in Europe in the 21st century.
At a news conference with Mr Yatseniuk, Mr Hague said: "If this situation cannot resolve itself, if Russia cannot be persuaded to respect the sovereignty and territorial integrity of Ukraine, there will have to be other consequences and other costs."
Mr Hague added: "The UK is not discussion military action, our concentration is on diplomatic and economic pressure."
Prime Minister David Cameron will later chair a meeting of the National Security Council on the "British and international response to the grave situation in Ukraine", where he will press for a European summit on the crisis.
European foreign ministers are holding an emergency meeting on Ukraine in Brussels to table a joint response to the military incursion.
Mr Yatseniuk heads a pro-Western government that took power in the former Soviet republic when its Moscow-backed president, Viktor Yanukovych, was ousted last week.
US Secretary of State John Kerry will visit Kiev on Tuesday to show "strong support for Ukrainian sovereignty".
Meanwhile, Ukraine launched a treason case against its new navy chief after he switched allegiance to the pro-Russian Crimea region .
Rear Admiral Denis Berezovsky was appointed head of Ukraine's navy on Saturday.
But a day later he appeared before cameras, alongside the pro-Russian prime minister of Crimea's regional parliament, saying he had ordered Ukrainian naval forces there to disregard orders from "self-proclaimed" authorities in Kiev.
Russian President Vladimir Putin on Saturday won parliament's authorisation to use force in Ukraine.
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