Leaders from the world’s 20 largest economies arrive Monday on the Indonesian island of Bali for a post-pandemic reunion chilled by Sino-US rivalry and overshadowed by a superpower seat between Joe Biden and Xi Jinping.

As people around the world feel the bite of stratospheric food and fuel prices, Ukraine is mired in conflict and the threat of nuclear war looms a looming veil, G20 Presidents and Prime Ministers will see what, if anything, they can do about it.

It is the largest gathering of the group of leaders since the pandemic began.

But this is not a loving reunion.

Over the past three years, the rivalry between China and the United States has sharply intensified as Beijing has grown more powerful and confident to replace the US-led order that has reigned since World War II.

Monday’s face-to-face meeting between Biden and Xi on the sidelines of the G20 has the atmosphere of the icy Cold War conclaves between American and Soviet leaders in Potsdam, Vienna or Yalta that decided the fate of millions.

Biden has spoken about the meeting that laid out each country’s “red lines” in hopes the contest won’t lead to confrontation and conflict.

US National Security Advisor Jake Sullivan said Biden will be “absolutely straightforward and direct” with Xi and expect the same in return.

Officials say he will also urge China to rein in ally North Korea after a record-breaking spate of missile tests raised fears Pyongyang will soon conduct its seventh nuclear test.

Xi may not be in the mood to help. He enters the gathering buoyed up, having recently secured a landmark third term that cemented him as the most powerful Chinese leader in generations.

Meanwhile, Biden was bolstered by the news that his Democratic Party had retained control of the US Senate after performing better than expected in the midterm elections, though his domestic politics remained feverish.

There will be one conspicuously absent from the table – Russian President Vladimir Putin.

His botched nine-month-old invasion of Ukraine has made the trip to Bali logistically difficult and politically tense.

With members of his inner circle at loggerheads and his once-iron inner authority eroded, Putin opted instead to send veteran Foreign Minister Sergei Lavrov.

Officially, neither the war in Ukraine nor Putin’s dark threats about the use of nuclear weapons are on the agenda of the summit.

But while the ex-KGB man won’t be at the summit table, his war will certainly be on the menu.

Rising energy and food prices have hit richer and poorer G20 members alike – and both are directly fueled by the conflict.

There will likely be pressure on Russia to extend a deal allowing Ukrainian grain and fertilizer shipments through the Black Sea when the current deal expires on November 19.

Biden and his allies would also like the G20 to at least make it clear to Putin that nuclear war is unacceptable.

Even this once-uncontested position is likely to be blocked by a mixture of Russian opposition and Chinese reluctance to break ranks with its ally in Moscow or give Washington a victory.

In a recent meeting with Chancellor Olaf Scholz, Xi said a nuclear war cannot be won and should never be fought.

Ryan Hass, a former director for China at the US National Security Council, said Xi “is not likely to be as magnanimous in his meeting with Biden.”

“He’s not going to want to be perceived as complying with a request from Biden, whether it’s related to Ukraine, the use of nuclear weapons, North Korea or any other issue,” Hass told AFP.

The G20 – a disparate and lumbering grouping formed in 1999 after the Asian financial crisis – has always felt most comfortable discussing finance and economics rather than security.

Moscow wants it to stay that way.

“We categorically reject the politicization of the G20,” Russia’s foreign ministry said on Sunday, offering a taste of what leaders might hear from the notoriously indomitable Lavrov.

“We are convinced that the G20 is destined to deal specifically with socio-economic issues.”

Host Indonesia — still wary of favoring either China or the United States — is not confident leaders will be able to break the deadlock.

A series of G20 ministerial meetings leading up to the summit failed to agree on a final joint communiqué – a procedural-sounding tradition that can be important in fostering cooperation.

“Honestly, I think the global situation has never been so complex,” Indonesian government minister Luhut Binsar Pandjaitan said on the eve of the summit.

“If the leaders (of the G20) don’t come out with a communiqué at the end, that’s fine.”