Donald Trump and Vladimir Putin had a brief meeting on the sidelines of the G20 summit, the White House and a Kremlin aide have confirmed.
Responding to questions about the US president's interactions with his Russian counterpart, White House press secretary Sarah Sanders told reporters: "As is typical at multilateral events, President Trump and the First Lady had a number of informal conversations with world leaders at the dinner last night, including President Putin."
The move comes after a planned face-to-face discussion between the two leaders was cancelled amid rising tensions over the Russia-Ukraine conflict.
Meanwhile, European officials confirmed that all nations present for the meeting in Buenos Aires, including Mr Trump’s, had agreed to reforming the World Trade Organisation (WTO).
Despite resistance from the US, EU representatives said they were optimistic and that progress had been made towards a final statement from the summit that acknowledges problems with the World Trade Organisation, but also commits to reforming it.
Officials said the US was the main nation holding back nearly every issue, although there were concerns from Australia about the statement being too soft on migration, and from Turkey about it pushing too far on climate change.
The US president has previously criticised the WTO and taken aggressive trade policies targeting China and the EU.
To appease Mr Trump, mentions of rising protectionism were cut from the statement, and mentions of migration were kept to a minimum.
They also agreed on climate change language that lays out the fact that 19 of the G20 leaders support the Paris climate agreement and efforts to cut emissions, but the US does not.
The leaders also expressed support for the upcoming UN climate meeting in Poland that will attempt to sort out how countries stick to the terms laid out by the Paris agreement.
After all-night discussions there was talk of a “breakthrough” as a six-page draft statement emerged saying the 20 countries support the international trading system, but think the current system needs fixing.
“There were moments when we thought all was lost... moments when we spent two hours on one sentence,” said one European official.
The diplomats said Russia had been particularly constructive, supporting international efforts on both trade and climate.
Outside the conference, however, Russia has been mired in controversy over its military actions in Ukraine and political interference abroad.
Previously a Russian spokesperson stated that Mr Putin and Mr Trump “said hi to each other” at the meeting, but they did not shake hands or engage beyond that.
The last minute decision to call of their meeting was seen by many as a tactical decision as fresh controversy swirls around Mr Trump’s financial ties to Russia.
However, the Kremlin had always maintained that they had not received any official notice from the White House calling off the meeting and that an informal discussion was always set to go ahead.