President Barack Obama spoke briefly with Russian President Vladimir Putin on Sunday as an economic summit got under way in Peru.
The two leaders were seen chatting as reporters were allowed in briefly for the start of the opening session of the Asia-Pacific economic co-operation summit in Lima.
They stood off to the side together momentarily with aides close by before shaking hands and then taking their seats around a table.
The White House said the conversation lasted about four minutes and that Mr Obama encouraged Mr Putin to uphold his country's commitments under the Minsk deal aimed at ending the Ukraine conflict.
Officials also said Mr Obama called for US Secretary of State John Kerry and Russian Foreign minister Sergei Lavrov to keep working in initiatives with other countries to lower violence in Syria and alleviate suffering.
The short interaction came amid intense speculation about whether Donald Trump's election as president might herald a more conciliatory US approach to Russia.
Under Mr Obama, the US has enacted severe sanctions on Russia over its aggressive behaviour in Ukraine and has sought unsuccessfully to persuade Moscow to stop intervening in Syria's civil war to help prop up Syrian President Bashar Assad.
Mr Trump and Mr Putin have already signalled they may pursue a less antagonistic relationship after the president-elect takes office in January.
In a phone call shortly after Mr Trump was elected, Mr Putin congratulated him and expressed readiness for a "partner-like dialogue", the Kremlin said.
In the run-up to the election, the US accused Russia of trying to interfere in the election, including by hacking into Democratic Party email systems.
Mr Obama had raised concerns directly to Mr Putin ahead of the election about Russian hacking and the US also registered complaints through a hotline set up to avert accidental nuclear war.
Throughout the campaign, the Kremlin insisted it had no favourites and rejected the claims of interference in the US election.
The meeting came as Mr Obama prepared for separate talks with the leaders of Australia and Canada before wrapping up the final foreign trip of his presidency.
Both countries helped negotiate a multi-national trade agreement with the US and nine other Pacific Rim countries.
Congress is unlikely to ratify the deal, dealing a blow to Mr Obama's once high hopes of having the agreement become part of his presidential legacy.
Mr Trump says trade deals can hurt US workers and he opposes the Trans-Pacific Partnership (TPP) agreement.
As well as participating in meetings on Sunday with other world leaders attending the event in Lima, Mr Obama was sitting down with Prime Minister Malcolm Turnbull of Australia, a US ally and partner in the TPP deal.
The president also planned to speak with Canadian Prime Minister Justin Trudeau, whose nation is another TPP partner.