JERUSALEM — A senior settler official says that work has begun on up to 600 new homes in West Bank settlements since Israel lifted its curb on such construction Sept. 26, mirroring recent findings by The Associated Press and the Israeli watchdog Peace Now.

Foundations are already being dug for at least 350 apartments, while construction of another 200 to 250 homes is in more preliminary stages, the official said Sunday. A second settler official said he believes some of the construction is already more advanced, and that out of the total being built, 400 to 500 apartments have reached the stage of foundation work.

Both officials are familiar with the construction and spoke on condition of anonymity because they are not authorized to release figures on the delicate topic — which has stalled U.S.-led peace talks and brought significant pressure on all sides to find a diplomatic solution.

Assessing the extent of post-freeze construction is difficult because Israel's government has declined to release information, and settlement officials generally won't provide detailed data.

Peace Now, which is conducting an extensive survey of building activity, has reported that work has begun on at least 600 new homes since restrictions — which Israel self-imposed in November 2009 for a predefined 10-month period — were lifted.

The AP count found that — as of early last week, about three weeks after the settlement curbs expired — work had begun on at least 544 apartments, including infrastructure, leveling ground and digging foundations.

The count was based on visits to 16 settlements and interviews with several settlement mayors who were asked about housing starts in their areas, but did not always elaborate on the stages of construction.

The building spurt of the past weeks — whatever its exact extent — compares to a total of just under 1,900 settlement housing starts in all of 2009, or 36 per week, as reported by the government. Comparing cases where foundations are being dug only, the figure of 500 in recent weeks would be about three and a half times the previous pace.

Peace Now researcher Hagit Ofran said she estimates that the pace is at least two and up to four times faster than before.

Part of the difficulty in nailing down the comparison to official data is that the government provides only delayed and periodic updates and does not start counting until construction progresses from leveling land to digging foundations.

Ofran said she believes construction tends to proceed very quickly these days from preliminary stages to foundation work because settlers and contractors are concerned about the possibility of a renewed freeze.

When building restrictions were imposed last November, contractors were allowed to continue building settlement houses whose foundations had already been poured. In this way — with the addition of allowing "exceptions" to the freeze on new starts — construction actually proceeded at a fairly brisk rate throughout the moratorium.

Ofran said that during the moratorium, settlers had prepared well for the resumption of construction. "It is not a surprise, because we knew this was coming," she said of the building spurt. "Unless the government imposes a freeze, the settlers will continue to build."

Israeli Prime Minister Benjamin Netanyahu has said any new construction would be kept to a minimum, but has not elaborated. Settler leaders have complained that the government is holding up several major construction projects.

Palestinian President Mahmoud Abbas says he will only resume talks once building restrictions are reimposed, arguing there is no point negotiating while Israel continues to build on land the Palestinians want for a future state.

About 300,00 settlers already live among 2.5 million Palestinians in the West Bank, and another 200,000 Jews live in east Jerusalem — both of which Israel captured in the 1967 war and are claimed by the Palestinians for their state.