Taiwan has a limited status in some international organizations under the name "Chinese Taipei" (this name greatly angers Taiwanese ultranationalists so I use it whenever possible), but the UN recognizes it as part of China.
There's a video of the UN voting on the PRC's membership to the exclusion of Taiwan, the entire room laughs when America casts its vote and there's an interview somewhere with a RoC diplomat whining about their "true democracy and freedom" despite the RoC being a one-party white terror regime.
I looked into it a little. The meeting records (see A/PV.1976 below the video) states that they are voting on A/L.632, which is:
The General Assembly,
Recalling the provisions of the Charter of the United Nations,
Decides that any proposal in the General Assembly which would result in depriving the Republic of China of representation in the United Nations is an important question under Article 18 of the Charter.
Article 18, §2:
Decisions of the General Assembly on important questions shall be made by a two-thirds majority of the member present and voting.
So, indirectly they are trying to split them. But the vote is not directly on that.
the americans had previously supported several draft proposals to have the prc on the unsc while also recognizing the roc with their own separate seat. on the day of this vote the assembly was just about to fully recognize the prc as china's representative. so I think it's fair to say that the eleventh hour american proposal to add a 2/3 supermajority requirement to any measure "depriving" the kmt of representation was effectively a vote on the un splitting china
@ComradeEd@lemmygrad.ml@satori@hexbear.net
Having gone through my own reading rabbit-hole on UN diplomacy in the past, I can clarify: The vote was on passing the "important question" scheme that the US first devised in 1961. Every time a motion in the UNGA was put forth to restore the UN seat to China, the US inserted a preliminary amendment to have the motion considered a "important question," which would require a supermajority rather than a simple majority for it to then pass. This blocked China's membership for 10 years until 1971. This is why the vote in the video has the US and its underlings voting in the affirmative and why the Assembly laughed, because by the US' turn to vote, it was already clear that the UNGA majority would reject the supermajority amendment and thus be able to restore China's membership.
The end came abruptly for the Taiwanese delegation. On October 26, 1971,
the General Assembly narrowly rejected the “important question” resolution,
which would have required a two-thirds majority to replace Taiwan with the
Communist government. Anticipating the inevitable next step, the Taiwanese
delegation walked out of the General Assembly moments before the lopsided
vote that formally evicted them. In that instant, Chiang Kai-shek’s government
lost all rights at the United Nations, including the coveted council seat. It was
just as well that the Taiwanese had left. Many delegations broke into wild
applause—and even dancing—as the results were announced. Finally, after
twenty-five years of exclusion. Communist China would be in the inner
sanctum.
Bosco, D. 2009. Five to Rule Them All: The UN Security Council and the Making of the Modern World. Oxford.
Not exactly "eleventh hour", it was submitted on the 29th of Sept, 4 days after the Albanian (et al.) proposal on the 25th of Sept. A truely eleventh hour proposal can be seen with the Saudi Arabian A/L.638 submitted on the day of the vote (25 Oct.)
Also... From A/PV.1976:
Mr. MALILE (Albania):
[...]
73. The explanations we have heard here concerning draft resolution A/L.632 are completely unfounded. This draft is basically an integral part of the anti-Chinese attempt of the United States of America to legalize its "two Chinas" plot and is designed to sabotage the approval of the draft resolution of the 23 States, including Albania [referring to A/L.630, which would expel the RoC and invite the PRC. It became the draft that was adopted]. The content of such a draft is illegal. It seeks to open the way to the United States manoeuvre aimed at involving the United Nations in the domestic affairs of the Chinese people, which is the aim of draft resolution A/L.633 [keeping the RoC in the UN, but replacing it with PRC on Security Council]. As has been clearly pointed out, that draft resolution is in flagrant contradiction with Article 18 of the Charter. It goes without saying that the Article cannot be applied to our draft resolution.