German Chancellor Angela Merkel and French President Francois Hollande have met with Russian President Vladimir Putin in a diplomatic push for peace in eastern Ukraine.
Merkel and Hollande on February 6 were presenting Putin with a new proposal to end the conflict between government forces and Russian-backed rebels that has killed more than 5,350 people since April and raised East-West tension to a level unseen since the Cold War.
Putin's spokesman, Dmitry Peskov, said the three leaders were meeting "eye-to-eye" in the Kremlin without other members of the visiting delegations or lower-level officials.
Details of the proposal brought by Merkel and Hollande have been kept under wraps, but Ukrainian President Petro Poroshenko said talks with the duo in Kyiv on February 5 raised "hope for a cease-fire."
Putin is facing growing Western pressure to abandon support for the separatists, who hold parts of two provinces and have gained ground in an upsurge of fighting that has killed hundreds of people in less than a month.
In Brussels, U.S. Vice President Joe Biden said that Russia "continues to escalate the conflict by sending mercenaries and tanks" into Ukraine.
Russia "cannot be allowed to redraw the map of Europe," Biden said, speaking alongside European Council chief Donald Tusk on February 6.
"This is a moment where the United States and Europe must stand together, stand firm," he said.
“Russia continues to escalate the conflict by sending mercenaries and tanks," Biden added.
Tusk said, "The European Union and the United States need to continue standing shoulder to shoulder, coordinate our efforts, and uphold the pressure on Russia for as long as necessary."
"We cannot compromise on Ukraine's independence, sovereignty, and territorial integrity," he added.
Putin's spokesman said on February 5 that the leaders would discuss "the fastest possible end to the civil war in southeastern Ukraine" -- wording that reflects Russia's claim that it is not involved in the conflict.
The separatists and the Kremlin blame Kyiv and the West for the renewed bloodshed, which followed a lull in the fighting in December, but the United States has called the recent escalation in fighting a "Russian-backed offensive" by the rebels.
NATO Secretary-General Jens Stoltenberg, arriving in Munch for a three-day annual security conference that will be dominated by the deadliest conflict in Europe since the Balkan wars of the 1990s, said reinforced rebels were on the attack.
"What we know is that the separatists have moved well beyond the original contact line and that they have also received substantial increased supplies of weapons during recent weeks," Stoltenberg said.
He said that "this has enabled them to launch new attacks and we have seen increased fighting along the whole of the original contact line. And that just underscores how serious and critical the situation in Ukraine is."
In Munich, British Defense Secretary Michael Fallon said that Western sanctions imposed on Russia over its annexation of Crimea in March and its support for the separatists will remain in place until it abides by commitments under a shattered cease-fire deal signed in September in Minsk.
"Anything that can help push, pull the Russians back to the negotiating table and ensure that the Minsk agreements are properly respected is to be welcomed, but we also need to keep up the pressure on Russia and make it absolutely clear that the current level of sanctions will continue to apply as long as the aggression in eastern Ukraine continues and that if it is increased then the sanctions too will be increased," he told Reuters
Ahead of her departure from Berlin, Merkel played down the chances of securing a truce.
"We don't know whether it will happen today or if further talks will be required,” she told reporters on February 6. “We don't know if these will be short talks today in Moscow or long ones, or if they will be final talks."
She also rejected reports that she was prepared to offer more territory to Ukraine's separatists, saying: "As German chancellor I would never, over the head of another country, in this case Ukraine, get involved in territorial issues."
In Paris, Hollande said he was heading for the talks with Putin with the aim of reaching an global agreement to end violence in Ukraine.
"Everyone knows that the first step must be a cease-fire, but it is not enough," he said. "We must get a comprehensive agreement."
The duo visited Kyiv on February 5 in the biggest push yet to resolve the 10-month conflict, which has killed more than 5,350 people since April 2014.
In Moscow, Putin aide Yury Ushakov said the Kremlin expected that Merkel and Hollande had taken the Russian president's own peace proposals into account.
Ushakov said Russia was "ready for a constructive conversation" aimed at stabilizing the situation, establishing a dialogue between the Ukrainian government and the rebels, and rebuilding economic ties between eastern Ukraine and Kyiv.
Those are goals Moscow has long espoused, and Ushakov made no mention of withdrawing troops or weapons.
Ukrainian Prime Minister Arseniy Yatsenyuk said Kyiv would not consider any peace plan that casts doubt on the country's territorial integrity, sovereignty, or independence.
Yatsenyuk made the statement after talks with U.S. Secretary of State John Kerry, who was also in Kyiv on February 5.
Kerry said Washington supported diplomacy, but "cannot close our eyes to Russian tanks crossing the border" into Ukraine.
He said that "Russia's continued aggression in the east" is the gravest threat facing Ukraine today.
Kerry demanded the withdrawal of all Russian troops and weaponry from Ukraine, and said U.S. President Barack Obama will decide soon whether to provide Ukraine with lethal weapons to fight the separatists.
In Washington, Republican Senator John McCain said U.S. lawmakers would write legislation requiring the United States to send arms to Ukraine if Obama did not do so.
White House spokesman Josh Earnest, meanwhile said, that the United States continues "to be supportive of ongoing efforts to try to find a diplomatic resolution" to the crisis.
Russian Foreign Ministry spokesman Aleksandr Lukashevich has warned that any U.S. move to send weapons to Ukraine would cause "colossal damage" to U.S.-Russian ties.
Germany and other European states remain fiercely opposed to sending arms to Ukraine.
The top NATO commander, U.S. Air Force General Philip Breedlove, said on February 5 that Russia continued to supply the separatists with heavy, state-of-the-art weapons, air defenses, and fighters.
Breedlove also cautioned that any move to give Ukraine lethal defensive weapons "could trigger a more strident reaction from Russia."
New NATO Command Posts
Meanwhile, NATO on February 5 agreed to immediately set up six command posts in eastern Europe and establish a spearhead force of 5,000 troops in response to Russian aggression in Ukraine.
NATO chief Jens Stoltenberg said the force would be available to deploy within two to seven days in a crisis.
The six command posts will be located in Bulgaria, Estonia, Latvia, Lithuania, Poland and Romania -- all former Soviet republics or satellites that are now in the EU and NATO.
The spearhead force will be backed up by two more brigades in order to keep reinforcements coming in a crisis.
In total, the NATO response force will be increased to 30,000 troops from the current number of 13,000.
On the ground in eastern Ukraine, a temporary, localized humanitarian truce for several hours on February 6 enabled some civilians to leave the besieged town of Debaltseve, the site of some of the deadliest fighting in recent weeks.
Separatist forces are trying to dislodge government forces from Debaltseve, which straddles a transport junction between the rebel-held provincial capitals of Donetsk and Luhansk.
The Ukrainian military said on February 6 that the rebels had carried out more than 100 attacks on army positions in eastern Ukraine over the past 24 hours, killing two soldiers and wounding 26.
With reporting by AFP, AP, and Reuters