Russia on Wednesday sentenced an Estonian intelligence officer to 15 years in jail, drawing ire from the EU after Tallinn said he was kidnapped at gunpoint on its territory.

A court in the western Pskov region, which borders Estonia, sentenced Eston Kohver on charges of spying, weapon possession and illegally crossing the border, his court-appointed lawyer, Yevgeny Aksyonov, told AFP.

Ukraine's pro-Western leadership and Russia traded blame on Tuesday for a sharp escalation in violence that threatened to see all-out warfare return to the former Soviet nation's separatist east.

Kiev and the insurgents on Monday reported the deaths of at lest 10 soldiers and civilians -- a dramatic escalation that sparked international condemnation and marked the worst bloodshed in more than a month.

U.N. Secretary-General Ban Ki-moon on Monday expressed serious alarm over the upsurge in fighting in Ukraine and called for urgent steps to de-escalate the violence.

Fierce clashes in east Ukraine killed at least 10 people in the past 24 hours, government and rebel officials said Monday, as Russia warned that Kiev could be preparing for a fresh offensive.

Russian President Vladimir Putin on Monday slammed alleged "external control" over Ukraine's government as he made his third visit to the Crimean peninsula since Moscow seized the region from Kiev last year.

"I am sure that despite all the current difficulties the situation in Ukraine will improve and Ukraine will develop," Putin said in televised comments during a meeting with local officials. 

The European Union on Monday expressed fears over a spike in violence in east Ukraine that claimed 10 lives as Russia warned Kiev could be preparing a fresh offensive.  

The single day death toll is the highest in over a month as government troops and pro-Moscow rebels accuse each other of gearing up for a renewed onslaught that would finish off an already tattered February truce.

Three civilians have been killed in east Ukraine as government forces claimed Saturday that shelling by pro-Russian separatists hit a record high since the start of a tattered truce in February. 

Authorities in Ukrainian-controlled territory along the frontline told Agence France Presse that shelling over the past day had killed two civilians and wounded 15 more. 

Two people were killed in another round of intense shelling between Western-backed Ukrainian government forces and pro-Russian fighters in the separatist east, officials from both sides said on Friday.

Ukraine's military spokesman Andriy Lysenko said one soldier was killed and six wounded in the past 24 hours of fighting across the mostly Russian-speaking war zone.

Ukraine and its biggest creditors failed to strike a deal Thursday on the second day of talks aimed at finding a workable solution for keeping the ex-Soviet country from hurtling into default.

A brief joint statement issued by Ukraine's finance ministry and the Ad-hoc Committee of Noteholders to Ukraine said the discussions were "detailed" but provided no immediate guidance as to the progress made.

Once thought dead and buried on the battlefields of Iraq, a muscular and militaristic "neoconservative" approach to U.S. foreign policy is making a comeback.

For most of the last decade, the "neocons" -- personified by former vice president Dick Cheney and ex-Pentagon boss Donald Rumsfeld -- have been out of office and out of fashion.

U.S. Secretary of State John Kerry called his Russian counterpart Sergei Lavrov on Thursday to express "grave concern" about increased separatist attacks in Ukraine, a senior State Department official said.

Washington has long accused Russia of fomenting unrest in a breakaway region of eastern Ukraine and has urged Moscow to help implement the terms of a shaky ceasefire deal while pushing for a political solution to the conflict.