(QHA) -

U.S. President Barack Obama and Russian President Vladimir Putin had a "brief encounter" in Beijing on the sidelines of APEC summit events on Monday night but did not have time to discuss the main issues between their two countries, a senior U.S. official said.

The informal conversation between the two leaders, who have been deeply at odds over Russia's role in the Ukraine conflict and its backing for Syrian President Bashar al-Assad, took place during events to welcome participants to the Chinese-hosted summit.

"They only had a brief encounter where they didn't have time to cover issues," the senior official said. "We'll let you know if they interact/cover issues tomorrow."

The White House has said that there are no plans for formal face-to-face talks between Obama and Putin at the Asia-Pacific conference or at the G20 summit later this week in Brisbane.

QHA