Vladimir Putin

The Kremlin said Putin noted in the telegram Saturday that despite the differences between the two countries, their relations remain important for global stability and security.

"Putin expressed confidence that by building a dialogue based on the principles of equality and mutual respect for each other's interests, Russia and the United States are able to find solutions to the most complex international problems and effectively counter global threats and challenges," the Kremlin said.

The war in Syria, which began with protests in March 2011, has killed more than 220,000 people. Russia, which has traditionally strong ties to Syria, has been seen as a key to a peaceful solution and has previously rebuffed suggestions that Assad's resignation could help end the war.

Syrian Foreign Minister Walid al-Moallem held talks with Russian Foreign Minister Sergey Lavrov on Monday then was whisked to the Kremlin to meet with Putin.

Putin told the Syrian envoy that Russia's "policy to support Syria, the Syrian leadership and the Syrian people remains unchanged."

The Russian leader, whose approval ratings reached an all-time high this month despite a bruising recession, said a "powerful army equipped with modern weapons is the guarantor of sovereignty and territorial integrity of Russia."

Speaking at Thursday's Kremlin meeting with graduates of Russian military academies, Putin also vowed to continue a sweeping military modernization effort that envisions the purchase of large numbers of new weapons.