PARIS — Support in Europe for a heightened Palestinian profile at the United Nations grew on Tuesday when the French government said it would vote in favor of the Palestinians’ bid for nonmember observer status, embracing a move that Israel and the United States have opposed.

The announcement by France, a permanent member of the United Nations Security Council, is the most significant boost to date for the Palestinians’ hopes to be granted the enhanced status in the world forum, and with that greater international recognition. Russia and China, two other permanent members, have also thrown their weight behind the Palestinian bid.

The backing of France and other countries appeared calculated to provide diplomatic ballast to the Palestinian Authority’s president, Mahmoud Abbas, a moderate whose Fatah party governs in parts of the West Bank. The effort came after the militant group Hamas, which controls the Gaza Strip, saw its credibility and standing with Palestinians rise after eight days of fighting with Israel.

But the French announcement was also a blow to Israel, whose diplomats have been working feverishly to try to ensure what they call a “moral majority” in the United Nations vote, meaning that even if a majority of nations voted in favor of the Palestinian bid, the major world powers would not.