The flag of the State of Palestine is flying at the United Nations.
It was raised in place earlier outside the organisation's headquarters in New York.
The General Assembly adopted five resolutions earlier this month on several topics - including the raising of flags by non-member observer states.
The resolution saw a vote of 119 in favour - including Ireland - eight against and 45 abstentions.
Australia, Canada, Israel, Marshall Islands, Federated States of Micronesia, Palau, Tuvaluand the United States all voted against the measure.
The General Assembly decided that flags of non-member observer states with permanent missions should be raised at headquarters and UN offices.
Palestine's observer at the UN said it was "a historic vote", and that the General Assembly had sent an important message to the Palestinian people at a critical time.
The UN Secretary-General Ban Ki-moon said: "This is a day of pride for Palestinians around the world. It is a day of hope".
"It is reminder that symbols are important - and that a symbol can lead to action in the right direction".
"We can be under no illusion that this ceremony represents the end goal. Achieving Palestinian statehood requires decisive action to advance national unity".
"I sincerely hope that a successful peace process will soon yield a day when we unfurl the Palestinian flag in its proper place - among the family of nations as a sovereign member state of the United Nations," he added.
Writing in The World Post, Palestinian Authority President Mahmoud Abbas said: "The sense of pride among the Palestinian people was overwhelming the day the world voted in favour of this landmark initiative".
"The General Assembly's vote confirmed again that we, the people of Palestine, are not alone in our quest for freedom, fulfillment of our rights and an end to decades of Israeli occupation and oppression".
Watch the moment below:
State of #Palestine flag flying @UN for the first time #PalFlag #PalestineFlag pic.twitter.com/KNUMmMZNeU
— State of Palestine (@Palestine_UN) September 30, 2015