The Islamic State jihadist group released a video on Tuesday purporting to show a young boy executing two men accused of working for Russian intelligence services.

The video shows the two men apparently being shot dead by the child after being interrogated on camera about their alleged attempts to infiltrate IS in Syria.

Three Ukrainian civilians and a soldier were reported killed on Tuesday in the latest wave of fighting across the country's separatist  east.

The Ukrainian military said another 10 soldiers were wounded in Grad rocket and mortar attacks by pro-Russian insurgents based around the eastern industrial city of Donetsk.

Russia has demanded an official explanation from France over its failure to deliver a Mistral-class warship due to concerns about Moscow's role in Ukraine, a military source said Tuesday. 

Moscow has written to France's overseas arms exporter in a move that could pave the way for legal claims against Paris, an unnamed official at Russia's Federal Service for Military-Technical Cooperation told state-run RIA Novosti news agency.

Ukraine said on Tuesday that a peace summit President Petro Poroshenko had hoped to convene to end his ex-Soviet republic's separatist uprising would require more preparation and talks with pro-Russian rebels.

The foreign ministers from Moscow and Kiev and their German and French counterparts met in Berlin on Monday to try to save a leadership meeting Poroshenko had proposed holding in the Kazakh capital Astana on Thursday.

Russian President Vladimir Putin has not confirmed his attendance at a crunch peace summit on Ukraine proposed for January 15 in Kazakhstan, the Kremlin said Monday. 

Kremlin spokesman Dmitry Peskov said that Putin's presence at the meeting -- which Ukrainian President Petro Poroshenko hopes will see four-way talks with the leaders of France and Germany -- depends on the outcome of a gathering of foreign ministers in Berlin on Monday.   

A key Syrian opposition official said in a statement on Friday that he has declined an invitation to take part in a Russian-led bid for new talks to end the conflict.

Moaz al-Khatib, ex-leader of the main opposition Syrian National Coalition, who recently established his own dissident movement, had visited Russia last year for discussions.

Russia has passed a controversial law banning transvestites, transsexuals and people with other "disorders"  from driving, prompting sharp criticism from rights activists, including a prominent Kremlin advisor.

The legislation, which took effect this week, says its aims at lowering the country's high death rate from road accidents.

Britain, Denmark, Estonia and Lithuania on Friday urged Brussels to prepare an EU-wide plan to tackle Russia's "propaganda campaign" amid tensions over Ukraine.

"Russia is rapidly increasing its disinformation and propaganda campaign, as an asymmetric response to Western economic power," the countries' foreign ministers said in a letter obtained by Agence France Presse.

The EU plans to give Ukraine a further 1.8 billion euros to help prop up an economy hit hard by a bloody conflict with Russian-backed rebels, European Commission head Jean-Claude Juncker said Thursday.

The 1.8 billion euros ($2.1 billion) in medium-term loans will help Ukraine "with the critical challenges" it faces and support the political and economic reforms the European Union believes are crucial to its future, a Commission statement said.

Ukraine's prime minister meets German Chancellor Angela Merkel on Thursday to press her to keep up the economic pressure on Russia at joint crisis talks with Vladimir Putin next week.

Arseniy Yatsenyuk's high-stakes trip to the European Union's biggest nation comes with the 28-nation bloc -- teetering on the verge of another recession -- mulling an easing of financial restrictions on Russia that have hurt both sides.