In a startling demonstration of support for Palestinian human rights from Capitol Hill, 10 Democratic senators wrote a letter to Israeli Prime Minister Benjamin Netanyahu on Wednesday urging him to halt the impending demolition of two Palestinian and Bedouin towns.

Israel has been actively planning the demolition of the West Bank Palestinian village of Susiya for months. Its government claims that the village is not authorized, despite the fact that it is in the occupied West Bank, which is internationally recognized as Palestinian territory.

For the past couple years, Sen. Dianne Feinstein, D-Calif., has been a lone voice on the issue, writing directly to Netanyahu to demand he halt the demolition. Feinstein’s efforts have been successful, as Israel has put off Susiya’s demolition multiple times.

But there are reports that Israel will begin demolishing structures in the village within weeks.

On Wednesday, Feinstein finally got some backup. She was joined by nine other Democratic caucus senators — Vermont’s Bernie Sanders and Pat Leahy, Illinois’s Dick Durbin, Delaware’s Tom Carper, Minnesota’s Al Franken, Massachusetts’s Elizabeth Warren, New Mexico’s Martin Heinrich, Oregon’s Jeff Merkley, and Hawaii’s Brian Schatz — in a letter from her office demanding Israel not demolish Susiya and the Bedouin town of Khan al-Amr.

The letter is unusually strong in its description of Israeli government behavior. “Instead of forcibly evicting these communities, we encourage your government to fairly re-evaluate Susiya’s professionally developed master plan and provide the residents of Khan Al-Ahmar equal building rights. Your government’s threats to demolish these communities are particularly distressing in light of the Israeli Civil Administration’s efforts to dramatically expand settlements throughout the West Bank,” it reads.

What makes the letter so remarkable is that there has been traditionally little criticism of Israeli human rights violations from members of Congress. Even some of the progressive senators who signed onto Feinstein’s letter had in the recent past defended Israeli government abuses.

For instance, in 2014, Sanders angrily defended his vote for a resolution backing up Israel’s actions in the Gaza war to a crowd at a Vermont town hall, citing the threat from Hamas to Israel.

But the past few years have also seen an explosion of activism aimed at pressuring Democrats to improve on this issue. After Palestinian-American activists were ejected from a Sanders campaign event in Boston in 2015 for carrying banners pressuring the presidential candidate on the issue, the Sanders campaign responded by apologizing. Sanders then went on to tap a top Palestinian-American activist — New York’s Linda Sarsour — as a surrogate and denounced Hillary Clinton’s unwillingness to criticize Israeli treatment of Palestinians at a New York debate. More recently, Sanders met with Palestinian human rights activist Issa Amro.

In 2014, Warren more or less repeated Netanyahu talking points about the war in Gaza, simply defending Israel’s right to self-defense as the country bombarded civilian infrastructure. She also literally bolted away from a question about Gaza at the liberal Netroots Nation conference.

But shortly after she offered a defense of Israel’s actions during the war, Warren was confronted at a town hall by activists who objected to her pro-Netanyahu stance. A Holocaust survivor asked the senator if she believed Palestinians also had a right to self-defense. Warren softened her tone, said that they did, and that the “direction we ought to be moving is not toward more war.” And more recently, Warren came out against legislation that would criminalize activists who boycott Israel or its settlements.

Lara Friedman, president of the Foundation for Middle East Peace, praised the Feinstein letter both on its merits and the political weight of having so many prominent senators joining on.

“The substance of the letter is terrific, and this list of signers makes a tremendous statement,” she said.

But she also insisted that Israel should cease the demolitions not just due to political fallout with the United States, but for moral and legal reasons as well.

“On the Israeli side, I hope they would take seriously the fact that, as [Israeli human rights organization] B’tselem has said, moving these people would constitute a war crime. I hope that Israel would take that seriously, separately from senators weighing in. I hope that they would take seriously that taking an action like this is counter to the values of a Jewish democratic state. This just adds to that.”