The hosting feud between the two nations has loomed over the COP30 conference in Brazil, where Bowen arrived Monday to try and break the deadlock in the final days of the gathering.

"We're fighting hard," Bowen told AFP after promoting Australia's bid in a public event directly next to Turkey's national pavilion, where he spoke about "winning that COP31 contest this week."

"We don't know how it'll go. But we're in it to win it."

Turkey and Australia both want to host the 31st Conference of the Parties, but under United Nations rules a winner can only be chosen by consensus -- meaning unless one withdraws, both could miss out.

Both countries insist they have the support needed and are refusing to back down, creating a stalemate that risks a bitter outcome in Belem where the current talks are underway.

Resolving the standoff was the minister's "top priority" in Belem, a senior Australian government source told AFP at the summit.

Bowen would seek a diplomatic solution through bilateral meetings with Turkish Climate Minister Murat Kurum, the source said.

- Rival bids -

Under COP rules, hosting duties rotate through five blocs of countries.

In 2026, that falls to the Western European and Other States -- two dozen countries mostly in Europe but also Turkey, Australia, Canada and a few others.

Australia has already rejected Turkey's offer to share the summit presidency, saying it was not feasible to split those complex duties between two distant countries.

Each insists they have support to win hosting rights, but it is understood there is no mechanism to force a vote in the absence of consensus.

Rival COP-hosting bids are not unprecedented but none has ever come down to the wire like this.

If successful, Australia would co-host with Pacific Island nations imperilled by rising seas and climate-fuelled storms and other disasters.

Tonga's head of delegation, Paula Pouvalu Ma'u, told AFP all Pacific Island nations were behind Australia.

"We're going to call it a Pacific COP," he said. "We're hopeful."

A UN Framework Convention on Climate Change (UNFCCC) official told AFP that if there's no decision in Belem, the COP bureau can technically make a decision later -- but it would still require consensus from the regional group.

With COP31 a year away, time is running out. Absent a clear winner, the summit will default to Germany, where the UNFCCC secretariat is based.

Canberra and Ankara are under pressure to break the impasse in Belem, a city in the Amazon rainforest where climate negotiations are into their second week.

Before leaving Australia, Bowen said the hosting standoff "will be decided at this conference, so it's not a matter of fighting on and on for months afterwards."