A passenger plane crashed in Siberia shortly after taking off Monday morning, killing 31 of the 43 people on board, Russian emergency officials said. The 12 survivors were hospitalized in serious condition.

The ATR-72, a French-Italian-made twin-engine turboprop, operated by UTair was flying from Tyumen to the oil town of Surgut with 39 passengers and four crew.

Russian authorities Sunday cordoned off Moscow's iconic Red Square and arrested 55 opposition supporters to prevent a rally against Vladimir Putin, who is due to take up his old Kremlin job.

All access roads to the central square were blocked off, an Agence France Presse reporter said, adding that police arrested dozens of supporters of the "Russia Without Putin" movement.

More than 70 Russian opposition activists, including writer Eduard Limonov, were on Saturday arrested during unauthorized gatherings in Moscow and St Petersburg.

In Moscow, around 300 people, some shouting "Russia without Putin" gathered in Triumfalnaya Square.

The world's biggest emerging powers on Thursday said dialogue was the only answer to the crises in Syria and Iran, seeking to buttress their economic heft with a unified diplomatic clout.

At their fourth summit, the leaders of the BRICS countries -- Brazil, Russia, India, China and South Africa -- also pushed for the creation of a new joint development bank as a counterpoint to Western-backed aid lenders.

Setting aside fears for a new arms race with the United States or the conflict in Syria, President Dmitry Medvedev took to Twitter Wednesday to reassure Russia on another burning issue -- the wellbeing of his cat.

Presidential pet Dorofey had not, contrary to press reports and frenzied Internet speculation, gone missing.

Russian President Dmitry Medvedev told Mitt Romney on Tuesday to use his head and stop reverting to Hollywood stereotypes after the U.S. presidential hopeful branded Moscow as Washington's top foe.

"I recommend that all U.S. presidential candidates, including the candidate you mention (Romney), do at least two things," Medvedev told Russian reporters on the sidelines of a nuclear security conference in Seoul.

Russian President Dmitry Medvedev said on Tuesday it was "short-sighted" to think that the crisis in Syria would be solved if President Bashar al-Assad agreed to Western calls to step down.

"To think that Assad's departure would mean the removal of all the problems is a very short-sighted position and everyone understands that if this happened the conflict would most likely continue," the ITAR-TASS news agency quoted Medvedev as telling Russian reporters at a summit in Seoul.

Beijing on Tuesday called on all parties in Syria to cooperate with the mediation efforts of Kofi Annan, as the United Nations and Arab League envoy held talks with Chinese leaders.

"We hope that all parties in Syria can cooperate with Mr. Annan's mediation efforts, in order to create conditions for the political settlement of the Syrian issue," foreign ministry spokesman Hong Lei told journalists.

NATO will announce the completion of the first stage of a controversial missile defense shield at a May summit that will not include Russian leader Vladimir Putin, its chief said Monday.

NATO secretary general Anders Fogh Rasmussen said the Western military bloc intended to announce the deployment of the first "interim" phase of a missile defense shield for Europe at the summit in Chicago.

Progressive Socialist Party leader MP Walid Jumblat praised on Monday the Syrian Muslim Brotherhood’s statement on the developments in their country, saying that it reflected the Sunni population’s openness to regional changes.

He said: “The Muslim Brotherhood demonstrated moderation, diversity, and equality.”