Russia's Foreign Minister Sergei Lavrov has said that Kiev's offer of dialogue with separatists in the east is a "step in the right direction, albeit very belated."
The official Twitter account of the Russian foreign ministry tweeted:
Russia and the United States exchanged strong-worded warnings over armed actions in Ukraine today.
Russian Foreign Minister Sergei Lavrov said that any armed action by Ukrainian authorities in the east of the country would undermine efforts at a diplomatic solution to the conflict.
Mr Lavrov made the warning during a call from US Secretary of State John Kerry, who in turn expressed concern about Russia's role in "inciting" trouble in eastern Ukraine, the Russian Foreign Ministry said in a statement.
The White House warned Russia against further military action in Ukraine after armed separatists seized government offices in the eastern city of Slaviansk today, saying the situation was reminiscent of what recently happened in Crimea.
Mr Lavrov said Ukraine was "demonstrating its inability to take responsibility for the fate of the country."He said that any use of force against Russian speakers in the east of Ukraine "would undermine the potential for cooperation."
The latest Ukraine crisis talks between US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov in Paris have ended after four hours, a US official has said.
Russia's foreign minister said Western sanctions have been "unpleasant" but not too painful overall.
In an interview due to air on Russia's Channel One today, Sergei Lavrov said: "The sanctions ... I don't want to say that they are laughable, I don't want to say that we don't care.
"They are unpleasant. But the fact they try to take those sanctions on a more personal level and present them as directed at certain people personally - it is clearly a desire to take revenge, we can see it with the naked eye".
Mr Lavrov and US Secretary of State John Kerry are scheduled to meet in Paris later today.
The legal process required to make Crimea part of Russia will be completed this week, Foreign Minister Sergei Lavrov said, two days after President Vladimir Putin signed a treaty to bring the Ukrainian region into Russia.
"Practical steps are being taken to implement the agreements on the entry of Crimea and (the Crimean port city of) Sevastopol into Russia," Itar-Tass news agency quoted Lavrov as saying.
"The legal process will be completed this week."
US Secretary of State John Kerry has told his Russian counterpart, Sergei Lavrov, that Russia must pull back its troops to their bases in Crimea, a US official has said.
Mr Kerry also reiterated that the White House regards today's referendum on the future of Crimea as illegal and the US government will not recognise the outcome.
Two of the EU's most senior officials, Jose Manuel Barroso and Herman van Rompuy, also released a joint statement calling the referendum "illegal and illegitimate".
Russian Foreign Secretary Sergei Lavrov has said the Ukrainian region of Crimea means more to Russians than the Falklands mean to British people.
He said the planned referendum in Crimea is in line with international law - a claim which US and EU leaders dispute - and argued that the region should be treated similarly to Kosovo, which was unilaterally declared independent from Serbia in 2008.
Mr Lavrov also flatly rejected reports which emerged today claiming that the Kremlin is planning to invade eastern Ukraine. He said Moscow has "no plans" to undertake such an operation.
Russia's Foreign Minister Sergei Lavrov is holding a news conference at the Russian Embassy in London after private talks with US Secretary of State John Kerry over the Ukraine crisis.
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