Syria's opposition National Coalition has accepted an invitation to hold talks in Russia with Foreign Minister Sergei Lavrov, whose country is a key ally of the Damascus regime, a coalition member said Wednesday.

Its deputy leader Hisham Marwa told AFP coalition chief Khaled Khoja received an invitation at the start of August to visit Moscow.

At least 16 people were killed and dozens injured when two buses crashed head-on in Russia's far eastern Khabarovsk region, officials said Wednesday.

The two intercity buses collided on the road between the cities of Khabarovsk and Komsomolsk-on-Amur. 

Russia pressed a claim at the United Nations Tuesday for an additional 1.2 million square kilometers (463,000 square miles) of Arctic shelf, an area of escalating international tension.

In a submission to back a 2001 claim at the U.N. Commission on the Limits of the Continental Shelf, Russia said research showed it had rights over the swathe -- an area the size of South Africa.

Russia's Foreign Minister Sergei Lavrov on Monday dismissed as "counter-productive" an announcement by Washington that it could take extra measures to defend U.S.-allied fighters in Syria.

At a news conference in Qatar, Lavrov condemned comments by the White House that it could take "additional steps" to protect allies in Syria and warned Bashar Assad's regime not to impede their actions.

A Swedish diplomat has been expelled from Moscow in a tit-for-tat move after the Scandinavian country recently kicked out a Russian diplomat, Stockholm's foreign ministry said Monday.

"Russian authorities have informed us that a diplomat at the Swedish embassy has to leave the country ... Russia has made it clear it considers this to be a response to the Swedish decision to expel a Russian diplomat," foreign ministry spokesman Johan Tegel told AFP.

An exiled former top ally of ousted Ukrainian leader Viktor Yanukovych on Monday launched a shadowy committee to "save" the war-torn country, pledging to bring down the current pro-Western government.

Ex-prime minister Mykola Azarov, wanted for corruption by Kiev after fleeing during last year's protests that toppled Yanukovych, called for public demonstrations and early elections in Ukraine at a press conference in a Moscow hotel.

Pictures of Russian President Vladimir Putin's spokesman flashing a watch worth an alleged $620,000 on Monday sparked controversy in the crisis-hit country.

Dmitry Peskov, who is given a broad remit to voice the views of the Kremlin strongman, was photographed wearing the pricey timepiece as he tied the knot with Olympic ice dancer Tatiana Navka on Saturday in the Black Sea resort of Sochi.

Russian security services said Sunday that they killed eight Islamists who had pledged allegiance to the Islamic State group and were behind attacks in the Caucasus region.

Special forces clashed with a "group of armed persons" in a mountain forest area near to Chechnya, said the National Antiterrorist Committee, without saying when the incident happened. 

A Russian airforce helicopter crashed during an air show on Sunday in front of thousands of spectators, killing one pilot, the latest in a string of military crashes.

The Mi-28N attack helicopter was participating in the show as part of a competition organized by the Russian defense ministry, Russian media reported from the event.

Finnish police said Saturday around 30 people were arrested after violence erupted at a Neo-Nazi march in central Finland.

The small protest by the Finnish Resistance Movement, a national socialist group, was relatively peaceful until some participants began targeting passersby and hindering police work,  police said in a statement.