The majority of American politicians are “afraid” to challenge the influential pro-Israel lobby in the United States, despite a growing willingness in Washington to clash with Israel and its supporters, a peace activist and author in California says.

The Obama administration’s endorsement of the recent nuclear accord between Iran and the P5+1 in the face of Israel’s fierce opposition is a “hopeful sign” of Tel Aviv’s declining influence in Washington, Miko Peled said.

“There’s a change in America and there’s willingness to finally engage the Israeli lobby in a substantive way,” Peled told Press TV on Saturday.

“Until now American politicians have always been afraid of the Israeli lobby because it’s very influential and most American politicians are still afraid,” Peled said.

Benjamin Netanyahu’s reelection as Israeli prime minister in March caused a significant shift in US foreign policy towards Tel Aviv, he noted.

“After Netanyahu was reelected in Israel, something very big changed here in America and there’s a much greater willingness to criticize not only the Israeli government but Israel as a people, as a nation because they voted for this lunatic once again, knowing full well that he’s a murderer, that he’s a criminal, that he has no intention of even to want peace.”

Peled made the remarks after US Secretary of State John Kerry said on Friday it would be “a huge mistake” if Israel decided to take military action against Iran over its nuclear program in the future.

"That'd be an enormous mistake, a huge mistake with grave consequences for Israel and for the region, and I don't think it's necessary," Kerry told NBC News when asked about a possible strike by Israel.

The American Israel Public Affairs Committee (AIPAC), the biggest Zionist group in the US, will deploy about 300 lobbyists on Capitol Hill next week to try to convince lawmakers to vote against the nuclear agreement with Iran.

AIPAC, along with some other pro-Israel advocacy groups, will spend approximately $20 million to fund a national television advertising campaign to inform the public “about the dangers of the proposed Iran deal,” according to officials in the pro-Israel camp.