U.S. President Obama sits after making remarks at the United Nations General Assembly at U.N. headquarters on September 28, 2015 in New York City.

“Russia’s military buildup in Syria, which amounts to direct occupation, especially at the coastal area, risks further fueling the conflict and acts as a prelude for partitioning our country“, warned Syrian rebel commanders with the Western-backed Free Syrian Army and the leaders of the Syrian National Coalition, a political umbrella organization.

“We would welcome a common platform for collective action against the terrorists”.

“In my opinion, provision of military support to illegal structures runs counter to the principles of modern global law and the UN Charter”, Mr Putin said.

Poroshenko stressed that Ukraine and its US and European allies need to be steadfast with Russia to make sure it lives up to the terms of the agreement to resolve the differences in eastern Ukraine, where pro-Russian separatists with support from Moscow have seized territory in the Donbass region and battled government forces.

Ban Ki-moon’s state of the world address to leaders from the UN’s 193 member states came shortly before Mr Obama, Mr Putin, Chinese president Xi Jinping and Iranian president Hassan Rouhani were to speak to the UN General Assembly.

“We have been providing assistance to legitimate government entities only”, Putin said.

“It’s obviously even more complex, I think, that we would have envisaged”, Power said. Rose spoke with Putin on a wide range of topics, including asking the president if he thought of Obama was “weak”, like many Republicans claim.

In remarks Sunday afternoon, he demanded strongmen like Syrian President Bashar al Assad provide stable governments for their citizens, warning that corruption will lead to events like the crush of Syrian refugees fleeing their country’s civil war.

One reason for the shift is that Mr Putin has stepped up his support for Mr Assad, moving troops and weapons into Syria, which have reportedly made their first bombing raids against IS targets. But a year after he announced his plan for airstrikes to combat Islamic State terrorists, the President will face pressure to explain the next steps in the unraveling situation in Syria.

The Russian President called Ukraine as Russia’s “sister country”.

The dramatic diplomatic gambit underlined how Russian Federation has seized the initiative on Syria, as U.S. Secretary of State John Kerry met his counterpart Sergey Lavrov to express his concerns.

Up to now, a key stumbling block for the United States and Russian Federation has been their disagreement over the future of Assad, with Russian Federation insisting he must be part of any political resolution and the USA saying he must go.