US Secretary of State Marco Rubio opened talks Friday with G20 counterparts including Russia's Sergei Lavrov, in meetings set to be fractious as wars in Ukraine and Iran, alongside surging energy costs, fan discord.
The foreign ministers' meeting in Atlanta, Georgia, takes place just days before crucial US midterm elections, setting the stage for a December G20 leaders' summit in Miami at President Donald Trump's Doral resort.
But ongoing conflicts have deepened rifts even as the United States seeks to focus on economic growth, trade imbalances and supply chain challenges in areas like energy and critical minerals.
Already, a traditional family photo planned for Friday morning was called off shortly before the two-day meeting started.
This came amid confusion over whether there would be two family photos, with and without Lavrov, diplomatic sources told AFP.
Some European officials have opted not to appear in photos with Russian delegations in earlier G20 meetings this year.
Rubio warned at an opening plenary session that the world faces "interconnected economic and geopolitical crises, many of which pose severe threats" to the global economy.
He urged the G20 to work together against threats including strains to global energy and food supply chains, and on freedom of navigation.
Still, few breakthroughs are expected this week from the Group of 20 economies -- which include China, India, Russia, Japan, Germany and France -- as officials face divisions over Moscow's war on Ukraine and fallout from the conflict with Iran.
Russia has been shunned by most of the West after its 2022 invasion of Ukraine, and Lavrov himself remains under international sanctions.
Rubio's encounter with Lavrov -- whose presence adds an additional layer of tension -- will be closely watched as Washington pursues diplomacy on Ukraine while seeking Moscow's cooperation on reining in fuel prices, a key campaign issue in the midterms.
A diplomatic source said that instead of a final declaration, this week's meeting is likely to conclude with the publication of a chair summary drafted by the United States.
The Trump administration is set to hand the rotating G20 leadership to Britain and sees the platform as having strayed from its core mission.
A US State Department official earlier stressed the importance of energy access for technologies such as AI and spoke of a "shared resolve to... keep critical sea lanes open to commerce without threats or tolls."
Global energy prices have rocketed since US-Israel strikes on Iran from late February triggered Tehran's blockage of the Strait of Hormuz.
"This is the last test case the G20 has, at least under the US G20 presidency, until Miami," Alisha Chhangani of the Atlantic Council told AFP. Its outcomes will affect how the December summit shapes up.
She expects Washington will seek to argue that security shocks are also economic shocks.
It will likely push for agreement on what "freedom of navigation" means within and beyond Hormuz, a crucial waterway for oil and gas transit, she said.
But this could face objections from China, which dissented against wording on free navigation in Hormuz and worldwide at an earlier gathering of finance ministers.
China's top diplomat Wang Yi will not be in Atlanta, and is instead sending his deputy, the US State Department said.
Meanwhile, the possibility of further escalation in the Middle East is mounting, with Israel threatening to strike Iran and Trump signalling he could attack after Tuesday's midterm elections.
The appearance of Lavrov, who plans to argue against international sanctions at the gathering, will likely frustrate European ministers, Chhangani said.
His meeting with Rubio comes ahead of fresh negotiations between Moscow, Kyiv and Washington in November.
It is not surprising, however, as Washington has welcomed Russian officials to this year's G20 events -- while excluding member South Africa -- and Trump has invited his Russian counterpart Vladimir Putin to Miami in December.
Trump has eased some sanctions on Moscow recently while touting a deal for Russia to sell diesel as prices soared, squeezing Americans.
The diplomatic source stressed that Russia's G20 presence "in no way legitimizes its actions."
All eyes will also be on US engagement with Brazil, whose foreign minister will be in attendance, after Washington granted entry to Flavio Bolsonaro following his defeat in Sunday's presidential election.