NUSA DUA, Indonesia - Secretary of State Antony Blinken called out Russia for blocking Ukrainian grain exports amid rising global food prices in a contentious closed-door session at a meeting Friday of the top diplomats from the world’s largest economies.

The Group of 20 meeting hosted by Indonesia on its resort island of Bali is the first time top U.S. and Russian diplomats have been in the same room since the invasion of Ukraine. The deep divisions between East and West - as well as North and South - at the conference hampered discussions on an array of pressing concerns, including rising energy and food costs, climate change, poverty and pandemic responses.

“To our Russian colleagues: Ukraine is not your country. Its grain is not your grain. Why are you blocking the ports? You should let the grain out,” Blinken said, according to a Western diplomat in the room who spoke on the condition of anonymity to relate events at the session.

Ukraine, the world’s fourth-largest grain exporter, has seen its exports shrink dramatically as fighting along its southern coast blocked its ports.

Blinken also disparaged Moscow’s contributions to the World Food Program, noting that it has provided only a fifth of 1% of the donations to the organization.

Russian Foreign Minister Sergei Lavrov was not in the room during Blinken’s remarks, having walked out of both plenary sessions as soon as his Western counterparts began to speak. But he lashed out at the Western diplomats present, accusing them of “rabid Russophobia, which they turn to instead of finding much-needed common ground on key issues on the global economy and finances, for which the G-20 was created.”

Ahead of the clash, Indonesia’s foreign minister, Retno Marsudi, implored her fellow diplomats “to end the war sooner than later and settle our differences at the negotiating table, not the battlefield.”

But signs of collaboration were sparse.

Blinken and other Western diplomats refused to be photographed with Lavrov for the traditional “family photo” that caps a G-20 conference and they ruled out bilateral meetings with Lavrov.

News events outside the meeting, including the Friday assassination of former Japanese prime minister Shinzo Abe and the Thursday resignation of British Prime Minister Boris Johnson, also jolted diplomats in attendance.

British Foreign Secretary Liz Truss, who was scheduled to meet Blinken and other G-20 diplomats, returned to Britain early as Conservatives there began the jostle to succeed Johnson as prime minister.

Japan’s foreign minister, Hayashi Yoshimasa, said he would attend a meeting with his U.S. and Korean counterparts but appeared poised to return to Tokyo immediately afterward.

The shooting, a rarity in Japan, where firearms laws are among the world’s strictest, prompted a wave of sympathy from ministers, including Blinken, who said he was “deeply saddened and deeply concerned” by the assassination attempt.

During the meetings, Marsudi urged diplomats to move past their differences to address the pressing problems facing the entire world.

“The question is, can we solve these global problems on our own? The answer is no. Global challenges require global solutions,” she said.

She emphasized that soaring fuel and grain prices were disproportionately affecting poor and developing countries and that the absence of a response from the G-20 would undermine the credibility of the multilateral system put in place after World War II.

“The current world situation makes people lose faith in multilateralism and its capacity to respond effectively to global challenges,” she said.

U.S. officials said they were determined not to let differences over Ukraine undermine the meeting, though they had hoped Indonesia would not invite Lavrov in the first place.

The large and diverse list of countries attending the G-20 meeting has traditionally resulted in Western countries facing more skepticism about their initiatives than at meetings of the more aligned G-7 industrialized democracies. Several of the G-20 countries have remained reluctant to join the West in condemning or sanctioning Russia over its invasion of Ukraine, including China, India, Brazil and South Africa.

As a result, U.S. officials organized meetings and joint statements with subgroups within the G-20, such as a meeting of representatives of Germany, France and Britain. Without anyone to push back, the allies put out a statement assailing “Russia’s unprovoked and unjustifiable war of choice” and Moscow’s “deliberate targeting of Ukrainian agriculture.”

Blinken will meet with at least one less friendly counterpart, however, in a bilateral discussion on Saturday with his Chinese counterpart, Wang Yi.

Lavrov met Wang on Thursday as part of a series of bilateral discussions with Asian leaders in advance of the conference. He is expected to meet with his Mexican, Brazilian and South African counterparts, as well.

In urging collaboration, Marsudi, the Indonesian minister, acknowledged it was an uphill battle. “Honestly, we cannot deny that it has become more difficult for the world to sit together,” she said.