(Adds Russian comment, background)
BEIJING, Nov 10 (Reuters) - U.S. President Barack Obama and Russian President Vladimir Putin spoke briefly on the sidelines of APEC summit events on Monday night but did not delve into the issues that divide their two countries, according to U.S. and Russian officials.
The informal contact 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.
Both sides played down the significance of the moment. "They only had a brief encounter where they didn't have time to cover issues," a senior U.S. official said. "We'll let you know if they interact/cover issues tomorrow."
Kremlin spokesman Dmitry Peskov also described a short exchange while holding out prospects for further discussions. Both will also attend a G20 summit in Brisbane later this week.
"There were no talks. They greeted each other," Peskov told Russian journalists in Beijing. "They exchanged a few lines. The presidents assume they will have a chance to talk on the sidelines (of the G20) in the coming days."
They would seem to have much to discuss but little chance of finding common ground. Communicating mostly by telephone over the past year, their occasional interactions have been described as tense as U.S.-Russia ties have sunk to a post-Cold War low.
Obama has insisted that Russia stop supporting pro-Russian separatists in eastern Ukraine, while Putin has dismissed the sanctions that the United States and the European Union have slapped on Moscow as counterproductive.
The two last had a brief informal meeting on the margins of D-Day anniversary celebrations in in Normandy in June.
White House officials had said in advance that there were no plans for formal talks between Obama and Putin at the Asia-Pacific conference or at the G20 summit. But they said they expected the two to find time to talk informally. (Reporting By Matt Spetalnick and Alexei Anishchuk in Beijing; additional reporting by Gabriela Baczynska in Moscow; editing by Ralph Boulton)