United States President Joe Biden will meet 18 leaders from the South Pacific when he visits Papua New Guinea in May, a top regional diplomat said on Saturday, as the U.S and China vie for influence in the region.

After the end of World War II, the South Pacific was seen as a relative diplomatic backwater, but it is increasingly the arena for powers to compete for commercial, political and military influence.

Papua New Guinea Foreign Minister Justin Tkatchenko said Biden would attend bilateral talks with his hosts and was “also having a meeting with the 18 Pacific Island leaders” from the Pacific Island Forum — a regional bloc of mostly small states that are scattered across the vast swathe of ocean.

Prime Ministers Anthony Albanese of Australia and Chris Hipkins of New Zealand will be among those attending.

Biden is set to become the first sitting US president in at least a century to visit Papua New Guinea when he touches down on 22 May.

He is also scheduled to attend summits of the Group of Seven leading economies in the southern Japanese city of Hiroshima and of the so-called Quad grouping — made up of Australia, India, Japan and the U.S — in the southeastern Australian city of Sydney.

U.S special envoy Joseph Yun said last week the U.S was playing “catch-up” after years of relative neglect that saw China’s influence soar across the South Pacific.

China recently signed a secretive security pact with the Solomon Islands that could allow Chinese troops to be deployed or based there.

In March, a state-backed Chinese company won a contract to develop the country’s international port in the capital Honiara, a major victory in Beijing’s quest to gain a strategic toe-hold in the South Pacific.

The region could prove vital in any possible military conflagration over Taiwan.

“We need to accelerate our catch-up,” Yun told the Hudson Institute. “Any high-level engagement is welcome,” he said before Biden’s Pacific meeting was confirmed.

“Let’s face it, it is strategic competition between China and us,” Yun said.

Biden’s trip may also put the finishing touches on a U.S-Papua New Guinea Defence Cooperation Agreement that would allow more joint training and the development of security infrastructure.

Washington is working to establish a joint naval facility at Lombrum, on Papua New Guinea’s Manus Island.

Construction started in mid-2020, said Australia’s Defense Department, which is also taking part in the initiative.

Four Guardian-class patrol boats are eventually expected to be based at the facility.