Relations with Australia were strained in 2006 when Prime Minister Sir Michael Somare was accused of having facilitated Julian Moti's escape to the Solomon Islands.^[57] Moti was wanted in Australia for serious alleged child sex offences. In retaliation, the Australian government banned Somare from entering Australia; all talks between Canberra and Port Moresby were suspended. In September 2007, relations began to thaw,^[58] and in December 2007, the new Australian Prime Minister, Kevin Rudd, met Sir Michael in Bali. Rudd announced what appears to be a normalisation of relations: "This relationship has been through a very difficult period in recent times. There has in effect been a freeze on ministerial contact between the two governments. I do not believe that's an appropriate way for the future."^[59]

• Australia has a High Commission in Port Moresby and a consulate-general in Lae.^[60]
• Papua New Guinea has a High Commission in Canberra and consulates-general in Brisbane and Sydney.^[61]

• Canada is accredited to Papua New Guinea from its High Commission in Canberra, Australia.^[62]
• Papua New Guinea is accredited to Canada from its embassy in Washington, D.C., United States.^[63]

The Independent State of Papua New Guinea and the People's Republic of China (PRC) established official diplomatic relations in 1976, soon after Papua New Guinea became independent. The two countries currently maintain diplomatic, economic and, to a lesser degree, military relations. Relations are cordial; China is a significant provider of both investments and development aid to Papua New Guinea.

In the late 2000s, Papua New Guinea began to strengthen its relations with Cuba. Cuba provides medical aid to the country.^[64] In September 2008, a PNG government representative attended the first Cuba-Pacific Islands ministerial meeting in Havana, aimed at "strengthening cooperation" between Cuba and Pacific Island countries, notably in coping with the effects of climate change.^[65]

• Cyprus is represented in Papua New Guinea through its High Commission in Canberra, Australia.^[66]
• Both countries are full members of the Commonwealth of Nations.

As of November 2005, relations with Pacific neighbor Fiji have been strained by revelations that a number of Fijian mercenaries have been operating illegally on the island of Bougainville, arming and training a rebel militia. Both Fiji and Papua New Guinea are full members of the Commonwealth of Nations.

Official diplomatic relations were established in 1976. Papua New Guinea is a member of the United Nations' Special Committee on Decolonization. The French government has noted what it calls Port Moresby's "moderate" attitude on the issue of the decolonisation of New Caledonia - which, like Papua New Guinea, is located in Melanesia.^[67] The French National Assembly maintains a Friendship Group with Papua New Guinea.

• India has a High Commission in Port Moresby.^[68]
• Papua New Guinea maintains a High Commission in New Delhi.^[69]

Western New Guinea (which consists of six Indonesian provinces: Papua, West Papua, Central Papua, Highland Papua, South Papua, and Southwest Papua) and Papua New Guinea share a 760-kilometre (470 mi) border that has raised tensions and ongoing diplomatic issues over many decades.^[70] Indonesia is represented in Papua New Guinea with an embassy in Port Moresby and a consulate in Vanimo. Reciprocally, Papua New Guinea has an Ambassador in Jakarta and a Consul-General in Jayapura.

Diplomatic relations between Japan and Papua New Guinea were established on 16 September 1975, the date Papua-New Guinea became independent. Japan maintains an embassy at Port Moresby. Papua-New Guinea is currently the largest recipient of Japanese foreign aid in the Pacific. Ministerial level visits are frequent between the two countries.^[71] Reciprocally, Papua New Guinea has an embassy in Tokyo.

• Mexico is accredited to Papua New Guinea from its embassy in Canberra, Australia.^[72]
• Papua New Guinea is accredited to Mexico from its embassy in Washington, D.C., United States.^[63]

• New Zealand has a High Commission in Port Moresby.^[73]
• Papua New Guinea has a High Commission in Willis Street, Te Aro, Wellington.^[74]

In March 2009, The Philippines and Papua New Guinea entered into a Memorandum of Understanding (MoU) that would enhance the cooperation between the two countries on the development of fisheries. The MoU will facilitate technology transfer in aquaculture development, promotion of shipping ventures, investments, technical training, joint research, and "strategic complementation" of each country's plans in the "Coral Triangle" – or the waters between the Philippines, Indonesia, and the Pacific Islands.^[75] In the same year, Papua New Guinea asked the Philippines for help in its pursuit of membership to ASEAN.^[76][77]

Both countries have established diplomatic relations in 1976.^[78] Papua New Guinea recognized Kosovo as independent from 3 October 2012 until withdrawing its recognition on 5 July 2018.

The Independent State of Papua New Guinea and the Republic of Korea have established diplomatic relations on 19 May 1976.^[79]

• Papua New Guinea and South Korea have good relations.
  • Papua New Guinean embassy in Seoul.^[80]
  • South Korean embassy in Port Moresby.^[81]
• South Koreans of Long-Term Residents in Papua New Guinea was about around 201 in 2019.

• Papua New Guinea is accredited to Spain from its embassy in Brussels, Belgium.
• Spain is accredited to Papua New Guinea from its embassy in Canberra, Australia.

• Papua New Guinea has an Honorary Consulate in Istanbul.^[82]
• Turkish ambassador in Canberra to Australia is also accredited to Papua New Guinea.^[82]

Papua New Guinea and the United Kingdom share King Charles III as their head of state. They have had relations since 1975 when Papua New Guinea gained independence from Australia.

• Papua New Guinea has a High Commission in London.^[83]
• United Kingdom has a High Commission in Port Moresby.^[84]

The U.S. and Papua New Guinea are signatories to the U.S.-Pacific Islands Multilateral Tuna Fisheries Treaty, under which the U.S. grants $63 million per year to Pacific Island parties and the latter provide access for U.S. fishing vessels. The U.S. also supports Papua New Guinea's efforts to protect biodiversity; the International Coral Reef Initiative is aimed at protecting reefs in tropical nations such as Papua New Guinea.

• Papua New Guinea has an embassy in Washington, D.C.^[63]
• United States has an embassy in Port Moresby.^[85]