Diplomatic efforts to find a solution to the Ukraine crisis have stalled and ended with "no agreements" being reached.
Russian Foreign Minister Sergei Lavrov met US Secretary of State John Kerry in Paris and left saying there would be further discussions on Ukraine "in days to come".
Mr Kerry urged Mr Lavrov to engage in direct talks with Ukraine as the pair met briefly before entering in further discussions with officials from France, Germany and British Foreign Secretary William Hague.
However, Mr Lavrov left the French foreign ministry without meeting Ukrainian foreign minister Andriy Deshchytsya.
The pair had earlier arrived at the building separately, which gave rise to hopes of them sitting down together to try and resolve the escalating crisis in Ukraine.
"We are all concerned at what is happening there," said Mr Lavrov.
"We agreed to continue those discussions in the days to come to see how best we can help stabilise, normalise the situation and overcome the crisis," he added.
Mr Kerry described the talks as "constructive" with "a number of ideas on the table" and said all parties were committed to finding a "remedy" to the crisis "through dialogue".
However, he warned: "We cannot and will not allow the integrity, the sovereignty of the country of Ukraine to be violated and for those violations to go unanswered.
"Russia made a choice and we have clearly stated that we believe it is the wrong choice - that is the choice to move troops into Crimea.
"Russia can now choose to de-escalate this situation and we are committed to working with Russia and together with our friends and allies in an effort to provide a way for this entire situation to find the road to de-escalation."
He said the US was committed to "making it happen as soon as possible" and said he expected to meet again with Mr Lavrov in Rome on Thursday.
IMr Deshchytsya said: "We want to keep good dialogue, good relations with the Russian people.
"We want to settle this conflict peacefully. We don't want to fight with Russia."
Mr Hague sad afterwards: "What is at stake is so enormous that it is very important for us to continue our diplomatic efforts. So in different places, through different channels, sometimes face-to face, sometimes by telephone, this will be continued over the coming days."
Wednesday's talks came to an end as Nato announced a full review of its cooperation with Russia - and said it would suspend plans for a joint mission linked to the destruction of Syria's chemical weapons.
It has been in talks with Russia about staging a possible joint mission to protect a US ship that will destroy Syria's chemical weapons arsenal.
At the same time British Chancellor George Osborne announced on Twitter plans to freeze assets of 18 Ukrainians accused of embezzling Ukrainian state funds.
Last week Switzerland, Austria and Liechtenstein said they were taking similar steps, but it is unclear whether the action involves the same 18 people.
Earlier, speaking at a news briefing with his Spanish counterpart Jose Manuel Garcia-Margallo in Madrid, Mr Lavrov said it was important for Russia to continue talks with Nato and EU leaders.
Mr Lavrov also said Moscow would like to see a de-escalation in tensions, sparked by Russian intervention in Ukraine's Crimea region.
But he added that "nobody has the right to be angry with Russia".
In Russia, President Vladimir Putin received a telephone call from German Chancellor Angela Merkel, the Kremlin said.
The two leaders "discussed possible scenarios for international co-operation in the normalisation of the social and political situation," it said in a statement.
Mr Putin told his cabinet he did not want the tensions to detract from economic co-operation with Moscow's "traditional partners".
However, British Prime Minister David Cameron warned there would be "costs and consequences" for Russia if it did nothing to ease the crisis in Ukraine.
He told Prime Minister's Questions the situation should not be a "tug of war" between Russia and the West.
Mr Cameron also had a telephone conversation with US President Barack Obama about the situation in Ukraine and tweeted: "We are united in condemnation of Russia's actions."
European Commission President Jose Manuel Barroso said the EU was ready to provide 11bn euros (£9.2bn) of financial support to Ukraine over the next couple of years.
The EU also said it could vote on Russian sanctions on Thursday if there is no de-escalation in the stand-off before then.
Mr Putin has previously said any Western sanctions against Moscow would be counter-productive.
America has already threatened sanctions, with a senior US official saying Washington is ready to impose them in days rather than weeks.
Mr Obama has also spoken to Mrs Merkel about a plan to end the stalemate.
Under the proposal, Russia would pull back its forces in Crimea to their bases in the peninsula and limit troop numbers to a Ukraine-agreed maximum of 11,000.
However, Mr Lavrov said that pro-Russian armed groups operating in Crimea were "self-defence" forces who do not answer to Moscow.
He added that Russian naval personnel in the region were in their normal positions.
A senior American official has said the plan would also see international monitors allowed in to ensure the human rights of ethnic Russians are protected.
Seen as an effort to offer Mr Putin a way out of the crisis without losing face, the plan would pave the way for direct talks between Moscow and the new Ukraine government with the potential for some international mediation.
The proposal would also see planned elections in Ukraine this May go ahead.
The US official added that Mr Obama had made clear to Ms Merkel that he would not attend a G8 summit scheduled for June in Sochi, Russia, if the situation in Ukraine had not changed.
Preparatory meetings about the summit have already been suspended.
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