LOS CABOS, Mexico - US President Barack Obama said Russia and China have "not signed on" to any plan for the removal of Syrian President Bashar Assad from power but that they recognize the dangers of an all-out civil war in the country.

Obama said Assad has lost all legitimacy and that it was impossible to conceive of any solution to the violence in Syria that leaves him in power.

He conceded he had failed to make a breakthrough with the leaders of Russia or China, despite intensive talks with both Moscow and Beijing, which have shielded Assad from tougher UN sanctions.

"I wouldn't suggest that at this point the United States and the rest of the international community are aligned with Russia and China in their positions, but I do think they recognize the grave dangers of all-out civil war," he told reporters at a Group of 20 summit in Mexico.

Please LIKE our Facebook page - it makes us stronger