Palestinian president Mahmoud Abbas has returned to the West Bank after winning upgraded UN status for the Palestinians, telling cheering crowds: "Yes, now we have a state."
"Palestine has accomplished a historic achievement at the UN," he added, three days after the United Nations General Assembly granted the Palestinians non-member state observer status in a 138-9 vote.
"The world said in a loud voice ... yes to the state of Palestine, yes to Palestine's freedom, yes to Palestine's independence, no to aggression, no to settlements, no to occupation."
Mr Abbas pledged that after the victory at the UN, his "first and most important" task would be working to achieve Palestinian unity and reviving efforts to reconcile rival factions Fatah and Hamas.
His comments came as UN leader Ban Ki-moon warned that Israeli plans for new settlements in east Jerusalem and the West Bank would deal an "almost fatal blow" to any prospect for peace with the Palestinians.
Israel's announcement about the 3,000 settler homes, whose planned location was not revealed, came in the wake of the UN vote to upgrade Palestine's diplomatic status.
"Settlements are illegal under international law and, should the E-1 settlement be constructed, it would represent an almost fatal blow to remaining chances of securing a two-state solution," Mr Ban's office said in a statement.
His spokesperson said Mr Ban expressed "grave concern and disappointment" at the bid that risks completely cutting off east Jerusalem from the rest of the West Bank.
The UN vote gives the Palestinians access to a range of international institutions, including potentially the International Criminal Court, and raises their international profile after years of stalled peace talks with Israel.
Mr Abbas was received with a full honour guard, descending from his car to walk along a red carpet at the Ramallah presidential headquarters known as the Muqataa, where he shook hands with waiting dignitaries.
While the Palestinians have expressed satisfaction and joy over the success of the bid, it has not been without repercussions.
Washington has warned it could withhold funds to the already cash-strapped Palestinian Authority, and Israel said it would not transfer millions of dollars it collects in tax funds for the Palestinians in response to the UN bid.