Palestinian leader Mahmoud Abbas officiated at the ceremony minutes after delivering a speech to the U.N. General Assembly in which he accused Israel of sabotaging efforts by the United States to broker a peace deal. Israel objected to the remarks.
Standing under the distinctive red, white, green and black banner in the U.N. headquarters' flower garden, Abbas said: "The day for raising this flag will come soon in Jerusalem, the capital of our Palestinian state" and "this day, every year, Sept. 30, will be the day of the Palestinian flag."
The Palestinians want East Jerusalem to be the capital of an independent Palestine.
On a gray, cloudy day on the banks of Manhattan's East River, a slight breeze was not enough to make the flag flutter once it was up.
The muggy air was pierced by the distinctive sound of ululation when several onlookers in the audience belted out the wavering, high-pitched trilling sound.
The General Assembly approved a Palestinian resolution this month saying flags of non-member states "shall be raised at (U.N.) Headquarters (in New York) and United Nations Offices following the flags of the member states."
The United States and Israel were among eight countries that
voted against the Palestinian-drafted flag resolution. Both said at the time that symbolic moves like raising flags do nothing to move the peace process forward.
In 2012, the General Assembly approved the de facto recognition of the sovereign state of Palestine. That followed a failed bid by the Palestinians to secure full U.N. membership.
Palestine and the Vatican are the only non-member observer states at the United Nations. The Vatican flag was raised at the U.N. on Friday, the day Pope Francis visited.