China's floating hospital, known as the Peace Ark, has weighed anchor from Port Moresby Harbour and set sail for Vanuatu, Fiji and Tonga before moving on to South and Central America.

Key points: The Peace Ark will bypass Pacific countries that give diplomatic recognition to Taiwan

The Peace Ark will bypass Pacific countries that give diplomatic recognition to Taiwan After its Pacific tour, the ship will set sail for the Dominican Republic

After its Pacific tour, the ship will set sail for the Dominican Republic China's Foreign Ministry rejects claims it is "meddling" in the Pacific

During a week docked in the Papua New Guinea capital, the People's Liberation Navy ship's staff treated more than 4,000 people.

Sorry, this audio has expired PNG: Floating Chinese hospital to win hearts and minds

China said the humanitarian mission is about helping its friends and allies, but security analysts say it's also a way of winning hearts and minds in an increasingly contested Pacific.

Independent Security analyst Alejandro Sanchez said the Peace Ark was modelled on similar vessels operated by the United States and formed part of China's "soft diplomacy" efforts in the Pacific and around the world.

"I think what the Chinese Government seeks to accomplish is that it wants to portray itself around the world not only as a global power, but as a friendly global power," he said.

The highest profile visitor to the ship was PNG Prime Minister Peter O'Neill, and Mr Sanchez said cementing relations with its allies was another key aim of the project.

But there is a hard edge to China's soft power, as Taiwan is increasingly finding.

The Peace Ark will pointedly bypass Pacific countries that give diplomatic recognition to Taiwan, including Tuvalu, Palau, the Marshall Islands, Solomon Islands, Nauru and Kiribati.

And after its Pacific tour, it will set sail for the Dominican Republic, a nation that switched allegiances earlier this year.

Peace Ark has eight operating rooms and offers a range of traditional Chinese medicine treatments. ( Reuters: Hugh Gentry )

The ship is staffed by more than 100 medical personnel and equipped with 300 beds and eight operating rooms, and even offers a range of traditional Chinese medicine treatments.

As well as treating the general public, the ship conducts academic exchanges with local hospital staff.

"The Peace Ark's mission is working. At the grass root level, I do believe the people that are benefiting from the treatment are happy," Mr Sanchez said.

"At the government level, it's just strengthening relations between China and its partners around the world."

China rejects claims of 'meddling' in the Pacific

Security analysts say the humanitarian mission is a way of winning hearts and minds in the Pacific. ( Reuters: Carlos Barria )

But while the Peace Ark may be making inroads for China's hearts and minds campaign it is still lagging a long way behind its biggest rivals.

"For every positive initiative that we hear about there is a negative one, like illegal fishing," Mr Sanchez said.

"The US has Hollywood, it has pop culture. Every person in Mexico, or Argentina, or Gabon, or Tanzania, or Fiji has watched at least one Hollywood movie," he said.

"Certainly initiatives like the Peace Ark are important initiatives, but there's still too much for China to do in order to catch up."

China has drastically ramped up its worldwide aid program in recent years. ( ABC News: Eric Tlozek )

Although China's presence has grown in the Pacific, China's Foreign Ministry has rejected claims it was "meddling" in the region, ahead of next week's AUSMIN summit.

Fairfax Media this week quoted Assistant Secretary of Defence for East Asia and the Pacific, Randy Schriver, as saying the US was caught "off guard" by China's campaign to exert influence over the island states of the South Pacific, and suggested the issue would be on the agenda at this year's Australia-US ministerial consultations.

US Secretary of State Mike Pompeo and Secretary of Defence James Mattis will host Australian counterparts Julie Bishop and Marise Payne in California on July 23 and 24.

Foreign Ministry spokesperson Hua Chunying said China hoped the meeting's real intention was "to promote regional peace and stability".

"We do remember that many state leaders in South Pacific countries have clarified that unlike some countries, China truly respects the willingness of people and governments in these island countries," she said.

