RAMALLAH, West Bank, Feb 9 (Reuters) - The Palestinian population in the West Bank, Gaza and Arab East Jerusalem grew by about 30 percent in the last decade, according to census data published on Saturday.

The significant growth in numbers to 3.76 million from 2.89 million, may spur calls in Israel to give up occupied land in the face of a perceived Arab "demographic threat" to the Jewish state.

Palestinians -- who want their own state in the Gaza Strip and the West Bank, which Israel captured in the 1967 Middle East war, with Arab East Jerusalem as its capital -- hope the census will boost their case in negotiations with Israel for an independent state.

Demographics is a thorny subject for the Jewish state. Israel's concern that Palestinians could eventually outnumber Jews if Israel kept control of the occupied territories was part of the thinking behind its decision to pull out of Gaza in 2005.

Israeli Prime Minister Ehud Olmert has cited such demographic concerns in advocating selective pullouts from the West Bank under a future peace deal. Israel wants to annex Jewish settlement blocs in that territory.

Around half a million Israelis live in East Jerusalem and West Bank settlements, branded illegal by the World Court.

Some 5.4 million Jews live in Israel and their birth-rate is lower than that of Israeli Arabs and Palestinians. Some 1.4 million Arabs reside in Israel.

The Palestinian Central Bureau of Statistics, which is under the administration of Palestinian President Mahmoud Abbas, said the census was conducted in all three areas after Israel and Hamas, which controls Gaza, dropped objections.

"Holding a census is actually about practicing sovereignty on the ground and among the people," PCBS president Luay Shabaneh told reporters. "Holding a census in Jerusalem was the biggest achievement for us."

Israeli officials had no immediate comment.

The previous Palestinian census was conducted in the West Bank and Gaza but had to rely on Israeli-supplied data for East Jerusalem, Shabaneh said. Hamas initially objected to a tally being taken in Gaza but relented following mediation.

"Today's results are de facto counting, actual counting," Shabaneh said.

The $8.6 million census project was co-funded by Australia, Norway, the United Nations Population Fund, the Netherlands, Switzerland and Saudi Arabia. It was launched in October and conducted by some 6,000 census-takers.