Israeli settlers have begun building new homes at a quick pace since the government lifted its moratorium on West Bank housing starts - almost 550 in three weeks, more than four times faster than the last two years.

And many homes are going up in areas that under practically any peace scenario would become part of a Palestinian state, a trend that could hamper U.S.-brokered peace talks.

According to an Associated Press count, ground has been broken on 544 new West Bank homes since September 26, when Israel lifted its 10-month freeze on most new settlement building.

The survey, while not comprehensive, marks the most extensive effort yet to quantify the construction. It was based on visits to 16 of the West Bank's more than 120 settlements as well as phone calls to more than four dozen settlements and interviews with construction workers and mayors.

"This figure is alarming and is another indicator that Israel is not serious about the peace process, which is supposed to be about ending the occupation," said Ghassan Khatib, spokesman for Palestinian President Mahmoud Abbas' self-rule government in the West Bank.

Prime Minister Benjamin Netanyahu has played down the new construction, saying it "has no real effect on the map of a possible (peace) agreement."

However, the renewed settlement construction has jeopardized peace talks relaunched only last month, with the Palestinians threatening to walk away if the freeze is not extended. And it could make the daunting task of partitioning the land even more difficult.

The building spurt of the past three weeks compares to average annual housing starts of about 2,000 in recent years, including just under 1,900 in 2009 and just over 2,100 in 2008, according to government figures. That is a rate of about 115 in three weeks, making the current pace more than four times faster.

The actual number is likely higher. When officials provided a range, the AP used the lowest figure. And it did not include 133 apartments a contractor said he was building in three settlements, because he did not say how many were already started.

The settlement watchdog Peace Now estimates there have been more than 600 housing starts and plans to release its own detailed report next week.

Much of the building activity witnessed by the AP involved leveling ground, and some settler leaders argue it is premature to define that as housing starts.

Asked about the AP count, a spokeswoman for the settler group Yesha Council said: "I prefer not to get into the numbers game because it's misleading."

About two-thirds of post-freeze work is preliminary and could be halted if the freeze is renewed, said the spokeswoman, Aliza Herbst.

Still, the scale of the construction is likely to harden Palestinian demands that a settlement freeze be reimposed as a condition for proceeding with the talks. Efforts by the United States to coax Israel into another building slowdown have so far failed.

In crisscrossing the West Bank, an AP team saw bulldozers and jackhammers tearing into rocky slopes in a number of locations.

One of the new building sites is in Karmei Tzur, a settlement with about 135 families located on the "Palestinian side" of the planned route of Israel's West Bank separation barrier, seen by some in Israel as the basis for drawing Israel's future border.

On Monday, jackhammers pulverized rocks on a barren slope as trucks carted off debris and heavy machinery drilled holes in preparation for pouring foundations. A woman answering the phone at the settlement's main office said 56 new apartments were being built.

A drive through Kiryat Arba, home to more than 7,000 Israelis, revealed two construction sites, for a total of at least 22 apartments, according to Palestinian laborers. And in the settlement of Revava, bulldozers were seen leveling ground along a slope. A contractor at the site said his company is building 83 apartments there.

In Kiryat Arba, Revava and many other settlements visited by the AP, officials declined comment on construction. In two places, armed guards denied reporters entry.

Other settlement officials were more forthcoming.

Avi Roe, who heads the Binyamin regional council, which represents about one-third of the West Bank settlements, said he is aware of at least 200 housing starts in his area.

Another 344 housing starts were confirmed by AP visits to settlements and interviews with mayors, construction workers and other officials.

Netanyahu imposed the settlement curbs last November in a bid to draw the Palestinians to the negotiating table. Netanyahu, who leads a rightist governing coalition, has said the slowdown was a one-time gesture.

The Obama administration has been trying to persuade Israel to extend the freeze and is expected to step up the effort after next month's midterm elections. Washington has floated the idea of a one-time two-month extension, during which Israelis and Palestinians would be asked to reach agreement on the future borders of a Palestinian state.

The Palestinians insist on a freeze for the duration of negotiations, saying two months is unrealistic to reach a border deal.

Nearly 300,000 settlers now live in the West Bank, along with 2.2 million Palestinians. Settlers have covered the territory - captured by Israel in the Six Day War in 1967, along with Gaza and east Jerusalem - with an increasingly intricate web of established communities and nearly 100 unauthorized hilltop outposts.

Despite the recent building spate, settlement leaders complain that approval for the largest construction projects is being held up. Israeli media reported this week that construction of more than 3,700 apartments awaits the signature of Defense Minister Ehud Barak, who has final say in the West Bank.

"I'm pessimistic about the near future," said Benny Kashriel, mayor of Maaleh Adumim, a settlement of 33,000 near Jerusalem. He said he hasn't been able to start new construction since the end of the moratorium.

A breakdown of an Associated Press count of new construction in West Bank settlements since Israel's moratorium on housing starts ended on September 26:

-- At least 200 housing starts in the Binyamin region, which contains one-third of the West Bank's more than 120 settlements, according to Avi Roe, the head of the regional council.

-- Ariel: 45 apartments being built by former Gaza settlers, according to Yitzak Vasana, a spokesman for the group.

--Beit Arieh: 25 apartments, according to Avi Naim, head of the settlement.

-- Barkan: 62 apartments, according to Shmuel Elad, head of the settlement.

-- Emanuel: 46 apartments, according to Rabbi Ezra Garashi, head of the
settlement.

-- Har Adar: 20 apartments, according to Aviram Cohen, head of the settlement.

-- Har Hebron, a group of 15 settlements: 50 apartments, according to regional council leader Zvi Bar-Hai.

-- Itamar: at least three, based on the comment by a settlement spokesman, Moshe Goldschmidt, that there were a few housing starts.

--- Karmei Tzur: 56, according to a woman answering the phone at the settlement office.

--- Kedumim: at least 12, based on a site visit and conversation with a land
surveyor.

--- Kiryat Arba: at least 22, based on a site visit and conversations with
Palestinian construction workers.

--- Oranit: at least three, based on a comment by a settlement official that there were a few housing starts.