The two-day meeting in Asheville, North Carolina, comes as the global economy is being buffeted by an energy shock triggered by the Iran war, faces rising tensions over China's huge goods trade surplus and is braced for how an investment surge in AI will ultimately play out.
Global debt levels earlier this year hit a record of nearly $US353 ($A493) trillion, leading to concerns about financial stability and prompting some investors to reappraise even traditionally safe havens such as US Treasuries.
"The world is awash in debt post-GFC, post-COVID, and the only way for us to get out of this is to grow our way out of this," US Treasury Secretary Scott Bessent said at the start of the meeting on Monday, referring to the 2007 to 2009 global financial crisis.
"I'm confident that a lot of the leaders are very receptive to this," he said.
As Bessent opened the meeting, some ministers were surprised and dismayed to see Russian Finance Minister Anton Siluanov sitting at the G20 table, the first time he has attended the forum in person since Russia invaded Ukraine in 2022.
Siluanov also held a bilateral meeting with Bessent that covered financial co-operation within the G20 framework, Russia's finance ministry said.
A US official said the focus of the bilateral meeting was on President Donald Trump's peace plan for Ukraine.
German Finance Minister Lars Klingbeil said Europe was preparing a further package of sanctions against Russia, but Siluanov's presence at the Asheville meeting sent a "quite troubling" signal for US co-operation with the effort.
"I would have wanted greater clarity from the American side that he should not be received here as a normal guest," Klingbeil said.
European officials also said they opposed appearing in the traditional "family photo" of G20 finance ministers and central bank governors, adding that this ultimately was taken without Siluanov.
His appearance marks a stark contrast from April 2022, when even his virtual participation in a G20 meeting in Washington drew broad condemnation of Russia's invasion of Ukraine and prompted a walkout by officials from the US, Britain, Canada and the European Central Bank.
Another issue that drew criticism was the US Treasury's decision to deny certain journalists media credentials to cover the event, including teams from Bloomberg News and specific reporters from the New York Times and the Wall Street Journal.
"I believe the press has a completely legitimate interest in reporting openly and freely on this G20 summit," Klingbeil said.
"I consider it unacceptable for journalists or entire editorial teams to be excluded."
A US Treasury spokesperson said that over 300 media were covering the event, including another New York Times reporter, and access comes with a "responsibility to report factual information consistent with established journalistic standards".
The Treasury also took the unusual step of inviting private-sector luminaries to participate in some of the G20 sessions on promoting stronger growth, reflecting the Trump administration's view that growth was best served by deregulation, producing more energy and fostering innovation.
Bessent told one of the sessions that global growth had underperformed its potential for too long and that causes can no longer include "policy failures of our own making".
He said the US Treasury had identified several impediments to growth that G20 countries needed to work on, including "excessive regulatory and administrative burdens, poorly designed financial incentives and tax systems, insufficient public and private investment, internal market fragmentation, and gaps in workforce skills and mobility".
