Despite support from diplomatic allies and the United States, Taiwan's participation in the UN System has largely been denied or limited due to pressure from China.

While the United States supported the ROC's claim to be the sole legitimate government of China, the Soviet Union was ally of the PRC.

Worried about the trend, the United States began in 1961 to put forth a motion that required not just a simple majority but a two-thirds margin to rule on the matter of representation.

[9] Following the Indonesian withdrawal from the United Nations in 1965, the PRC reduced its efforts to enter the UN, but it soon resumed the diplomatic push for membership.

[10]: 9  A number of former colonies joining the UN, as well as better relations with western countries following the Sino-Soviet split, allowed the PRC to gain enough support that a supermajority was not needed for a decision on its membership.

[10]: 7, 14  The PRC further enhanced its diplomatic efforts to cement the One China principle in the UN following the end of martial law in Taiwan and the introduction of democratic reforms in the late 1980s and 1990s.

In particular, rhetoric began to shift following the 2000 Taiwanese presidential election, when the Kuomintang (KMT) lost the presidency of Taiwan to the more independent-minded Democratic Progressive Party (DPP).

[7]: 252  Taiwan continued to maintain a policy of refusing to join an organization in which the PRC was a member ("the Chinese and the bandits would not co-exist") until the late 1980s, when it began to accept the concept of dual membership.

[7]: 252  Continued Taiwanese participation in Interpol is limited by strict conditions imposed by the PRC, including being referred to as "Taiwan, China" and being officially being part of the Chinese delegation with no voting rights.

[7]: 252  This relatively late PRC membership was due to resistance from the United States and Japan, which had significant influence in ADB and did not want Taiwan to become fully isolated.

[10]: 17–18 In 2008 Secretary General Ban Ki-moon rejected a Taiwanese membership application, stating that Resolution 2758 affirmed the One China policy.

[18] Every year from 1993 to 2006, UN member states submitted a memorandum to the UN Secretary-General requesting that the UN General Assembly consider allowing the ROC to resume participating in the United Nations.

[24] However, the application was rejected by the United Nations Office of Legal Affairs citing General Assembly Resolution 2758,[25] without being forwarded to the Security Council.

[30] A group of UN member states put forward a draft resolution for that autumn's UN General Assembly calling on the Security Council to consider the application.

[32] Nevertheless, Secretary General Ban Ki-Moon's statement reflected long-standing UN convention to deny the ROC representation and is mirrored in other documents promulgated by the United Nations.

For example, the UN's "Final Clauses of Multilateral Treaties, Handbook", 2003 (a publication which predated his tenure in Office) states: [r]egarding the Taiwan Province of China, the Secretary-General follows the General Assembly's guidance incorporated in resolution 2758 (XXVI)of the General Assembly of 25 October 1971 on the restoration of the lawful rights of the People's Republic of China in the United Nations.

[20][35] Shortly after this, the United States and the national governments of the European Union expressed their support for "Taiwan" (none of them recognises the ROC) to have "meaningful participation" in UN specialized agencies, such as the World Health Organization.

[41] In September 2011, Tuvaluan Prime Minister Willy Telavi made a statement at the 66th session of the United Nations General Assembly (UNGA).

An American Catholic school in 2021 changed and eventually dropped references to Taiwan in a year-old article before receiving approval to attend the United Nations Commission on the Status of Women.

World Bank President Robert McNamara indicated that PRC membership would be considered, but did not address the question of Taiwanese participation.

China, which claims Taiwan as its own territory but does not administer health policy across the Strait, blocked it from participating in the assembly following the election of Tsai Ing-wen as president in 2016.

[10]: 22 Due to Taiwan's successful response to the COVID-19 pandemic, its inclusion in the WHO gained international attention in 2020, with strong support from the United States, Japan, Germany and Australia.

[69] In addition, the Formosa Club, a platform for European and Canadian legislators, jointly with 926 lawmakers from 29 countries, signed a letter urging WHO Secretary-General Tedros Adhanom Ghebreyesus to invite Taiwan to participate as an observer in the WHA.

[74] Members of the organization takes annual trips to the United States to meet with legislators and representatives to the UN from Taiwan's diplomatic allies.

[75] In 2023, Alliance of Democracies Foundation executive director Jonas Parello-Plesner wrote an opinion piece in Politico to call for the UN to recognize Taiwan's voice.

[77] In 2015, Tsai Yu-ling, a Taiwanese national who wished to join a daily guided tour at the UN headquarters in Geneva, was denied entry after she showed her Taiwan passport.

During a separate press conference, French reporter Celhia De Lavarene revisited the issue and asked Dujarric if China was running the UN.

[82] Reporters Without Borders (RSF) also made a statement: Refusing journalists' accreditation based on their nationality or the geographical location of their media registration is clearly discriminatory and against the public's right to information.

[83]A UN spokesperson wrote to Voice of America that "the United Nations headquarters are open to individuals in possession of identification from a State recognized by the UN General Assembly.

[84] In May 2024, the same two reporters who were denied entry the year prior were asked to provide an official Chinese passport by the media credentials review committee.