Two Indian navy ships docked in Papua New Guinea on Wednesday, underscoring the strategic importance of the country to global superpowers the United States and China, and their allies.

The INS Kolkata guided missile destroyer and INS Sahyadri frigate will stay in PNG's capital Port Moresby for two days, an Indian embassy official said. The visit will "enhance maritime cooperation and security in the region", an embassy statement added. India currently holds the rotating presidency of the G20.

The ships will then join naval exercises in Australia as part of the Quadrilateral Security Dialogue, or Quad, a group that also includes Japan and the United States. The Malabar exercise begins on Friday.

The United States and its allies are seeking to deter Pacific island nations from forming security ties with China, a rising concern amid tension over Taiwan, and after Beijing signed a security pact with Solomon Islands. PNG struck a defence agreement with Washington in May.

Pacific island leaders, whose territories span 40 million square km (15 million square miles) of ocean, have said rising sea levels caused by climate change are their most pressing security priority.

The navy port call follows a visit by Indian Prime Minister Narendra Modi in May to Papua New Guinea, an underdeveloped but resource-rich nation north of Australia. Modi took part in a summit meeting of Pacific nations.

The leaders of both France and Indonesia, as well as senior U.S. and British officials, have also visited PNG in quick succession. U.S. President Joe Biden was forced to cancel a visit because of debt ceiling negotiations in Washington.

Michael Green, CEO of the United States Studies Centre at the University of Sydney, said it was not the first time the Pacific Islands have come to world attention during major transitions in international relations.

At the end of World War One, the islands "consumed attention" at the 1921-22 Washington Naval Treaties amid concern over Japan's access to an undersea cable, said Green, a former senior U.S. national security advisor.

After World War Two, the U.S. was "determined to keep the former Japanese islands out of the Communist bloc because they were critical to protecting the southern flank below Japan and above Australia," he said. With China's rise, Pacific Islands airfields and undersea cables have again come into play, he added.

China is PNG's largest trading partner. Director of the Pacific Islands Program at the Lowy Institute think-tank, Meg Keen, said the recent push by China into security has "raised concern among Western countries with strong national interests in the region".

"The U.S. is trying to secure a bilateral security agreement with PNG and show it is in the region to stay and will make a positive difference. To date its engagements have been modest," she said.

Pacific Island nations have welcomed the additional interest from the West but will continue to engage with China, she said.

"The Pacific will want more than Pacific frequent flyers, they want genuine partnerships that deliver results," she added. (Reporting by Kirsty Needham in Sydney; Editing by Miral Fahmy)