Russian President Vladimir Putin said on Sunday there was a "good chance" of resolving the conflict in Ukraine as Western leaders squarely blamed Moscow and threatened to slap more sanctions if it did not take action to end the crisis.

Putin was speaking at a G20 leaders summit in Brisbane where he has come under intense pressure.

Russia has denied any involvement in the conflict in Ukraine that has killed more than 4,000 people this year.

"Today the situation in Ukraine in my view has good chances for resolution, no matter how strange it may sound, but certain structures had been established on both sides that could handle the tasks they are facing better," Putin said before he left Brisbane ahead of the formal ending of the summit.

US President Barack Obama, Australian Prime Minister Tony Abbott and Japanese Prime Minister Shinzo Abe lined up together against Russia on Sunday, vowing to oppose what they called Moscow's efforts to destabilize eastern Ukraine.

Putin said Ukraine was never mentioned during the official G20 meetings, but was brought up at every meeting with other leaders he attended on the sidelines.

"Those discussions were very honest, meaningful and very helpful," Putin said.

"I spoke generally, a bit about sanctions in my private meetings, and there was a shared understanding that sanctions are bad for both countries, and we also talked about what should be done to get out of this situation," he said.

Reuters - AP