Non-member observer states are free to submit a petition to join as a full member at their discretion.
[2][3] Observer status is granted by a United Nations General Assembly resolution at some point in time.
The World Health Organization (WHO) Constitution does not recognise an observer status but the Rules of Procedure of its highest decision-making body World Health Assembly (WHA) give the Director-General right to invite observers to the annual Assembly meeting, provided that they are "States having made application for membership, territories on whose behalf application for associate membership has been made, and States which have signed but not accepted the Constitution."
All these efforts failed, mainly due to firm objections from the People's Republic of China (PRC) which does not recognize the ROC and considers Taiwan as one of its provinces.
This status only lasted for eight years and ended in 2016 following the election of DPP presidential candidate Tsai Ing-wen.