File photo: A man walks past the flags of the countries attending the Gulf Cooperation Council (GCC) summit at Bayan palace in Kuwait City on December 5, 2017. AFP
The GCC, in a letter to US Secretary of State Antony Blinken, called on Washington "to assume its responsibilities in responding to all measures and statements that target the Palestinian people".
The letter from the six-member GCC's foreign ministers also called on the United States "to play its role in reaching a just, comprehensive and lasting solution" to the Israeli-Palestinian conflict.
Israel's far-right Finance Minister Bezalel Smotrich, speaking earlier this month, said that the Palestinians did not exist as a people, comments that sparked outrage among Arab nations.
The US State Department said they had found Smotrich's comments "to not only be inaccurate but also deeply concerning and dangerous."
Smotrich is part of veteran Israeli leader Benjamin Netanyahu's hard-right government that took office in December.
The GCC ministers also denounced earlier remarks by Smotrich, calling for the Palestinian town of Huwara in the West Bank to be "wiped out" after two Israelis were shot dead there by an alleged Hamas militant in February, remarks he later walked back.
The GCC, whose foreign ministers met in Riyadh last week, includes the United Arab Emirates and Bahrain, which normalised relations with Israel under the US-crafted 2020 Abraham Accords, as well as Saudi Arabia, which has not.
Violence has intensified in the West Bank in recent months, which Israel has occupied since the Six-Day War of 1967.
On Tuesday, the State Department criticised a move by Israel's parliament to annul part of a law banning Israelis from living in areas of the West Bank evacuated in 2005, calling it "provocative" and in direct contradiction of promises made to Washington at the time.
Blinken, appearing before a Senate committee, also reiterated previous US pushback on Smotrich's comments about Palestinians, saying they do not reflect US values.