A large group of Democratic senators has called on Israeli Prime Minister Benjamin Netanyahu to take stronger action against rising settler violence and mass arrests of Palestinians in the occupied West Bank.

A letter signed by 45 of the Senate Democratic caucus’s 47 members expressed concern over reports of deadly attacks involving Israeli settlers. The lawmakers urged the Israeli government to protect Palestinian civilians and hold those responsible for violence accountable.

The senators warned that deteriorating conditions in the West Bank could further undermine regional stability and weaken prospects for a negotiated settlement between Israelis and Palestinians.

The appeal reflects growing concern among Democratic lawmakers over Israel’s policies in the occupied territory. It also adds political pressure on Netanyahu’s government as Washington continues to balance its support for Israel with criticism of actions that may intensify the conflict.

Israel has previously said that security operations in the West Bank are aimed at preventing militant attacks.