Russia will never become a dictatorship, Russian Prime Minister Vladimir Putin said Wednesday, as he continued his bid for a third term as president despite unprecedented protests against his rule.

"We have an open country and no matter what they say or write, no matter what scary statements they make about some sort of dictatorship, we don't have that and -- I hope -- never will," he told students of Tomsk Polytechnic University in Siberia.

Russia said Wednesday it was "open to constructive proposals" on Syria but remained opposed to any U.N. resolution that tried to force all nations to respect sanctions previously imposed by the West.

"We are open to constructive proposals that go in line with the set task of ending violence," Foreign Minister Sergei Lavrov said following talks with his Turkish counterpart Ahmet Davutoglu.

Britain, France and the United States on Tuesday condemned Russia's arms sales to Syria which they said was fueling President Bashar al-Assad's deadly crackdown on protests.

Britain's U.N. ambassador Mark Lyall-Grant called the Russian weapons sales "irresponsible," at a Security Council debate on the Middle East.

Gulf Arab states have decided to pull their observers sent to Syria as part of an Arab League mission out of the restive country, they announced in a joint official statement on Tuesday.

"Gulf Cooperation Council states have decided to follow Saudi Arabia's decision to pull out its observers from the Arab League mission in Syria," the GCC statement said.

A member of Russia's Parliament, Mikhail Margelov, said Monday that Moscow ran out of methods to stop the international push for Syrian President Bashar Assad to step down.

Russia's veto of a U.N. Security Council resolution on Syria "was the last instrument allowing Bashar Assad to maintain the status quo in the international arena,” Margelov was quoted as saying by Russia's Itar-Tass news agency.

A senior U.S. diplomat visiting Russia will press Moscow on a reported deal to sell Syria fighter jets, something Washington described as "quite concerning," the State Department said.

Jeffrey Feltman, the top U.S. diplomat for the Middle East, was in Moscow on Monday and Syria was "issue number one on his agenda," U.S. State Department spokeswoman Victoria Nuland told reporters in Washington.

Indian navy personnel will take command of the country's first nuclear-powered submarine in two decades on Monday after collecting the vessel near the Russian port of Vladivostok, an official said.

Syria has signed a $550 million (425 million euro) contract to purchase 36 Yak-130 advanced training fighter planes from Russia, the Kommersant business daily reported on Monday.

The deal was signed in December with Russia's Rosoboronexport state defense corporation, Kommersant cited a source close to the agency as saying, adding that production of the jets would begin once the advance payment was made.

Russia needs real political change, not a "survival mechanism" for the current regime, a Council of Europe Parliamentary Assembly delegation said Saturday.

The group, which observed last month's controversial parliamentary elections, was speaking in Moscow ahead of the presentation of its final report at a plenary session in Strasbourg on Monday.

Canada has expelled four Russian diplomats following the arrest last weekend of a Canadian soldier charged with leaking secrets to a foreign entity, Canadian media reports said Friday.

But in Moscow, the Russian foreign ministry denied the reports.