Although the actual buildings of the settlements cover just 1 percent of the West Bank's land area, their jurisdiction and regional councils extends to more than 42 percent, the group added.
Twenty-one percent of the land for these settlements was seized from Palestinian landowners, much of it after Israel's Supreme Court outlawed the practice in 1979.
Dani Dayan, chairman of the settlers council, said settlements control just 9.2 percent of the West Bank, not 42 percent.
"It's a political report by an organization that has been taken over the most radical anti-Israel elements," Dayan said. "The whole point is to sabotage the meeting between (Israeli Prime Minister) Benjamin Netanyahu and Barack Obama."
Netanyahu was en route Tuesday to Washington, where he was due to meet with Obama later in the day to discuss advancing peacemaking and other regional issues.
Some 300,000 Jews live in West Bank settlements and an additional 180,000 live in Jewish neighborhoods in east Jerusalem. Israel captured both territories from Jordan in the 1967 Mideast war, along with the Gaza Strip.
The Palestinians envision all three areas for a future state.