A broad range of U.S. Jewish figures have written to Prime Minister Benjamin Netanyahu to encourage him as peace talks are set to resume in Washington next week.

“We recognize that achieving a two-state solution will require a territorial compromise that provides for a Palestinian state without jeopardizing Israel’s security,” said the letter, initiated by the Israel Policy Forum and signed by 140 leaders of religious groups, donors and former luminaries of both the Republican and Democratic parties.

“That is why we applaud your understanding that one must be ‘willing to make painful compromises to achieve this historic peace,’” it said.

Netanyahu has said, since agreeing to U.S. Secretary of State John Kerry’s appeal to restart talks, that such compromise is necessary.

One of Netanyahu’s top deputies, Strategic Affairs Minister Yuval Steinitz, on July 25 told the British Daily Telegraph that a two-state solution was “the only possible solution” to the Israeli-Palestinian conflict.

It is not clear yet whether the Palestinians are ready to drop preconditions, among them Israel freezing settlement expansion, before starting talks.

“It is our hope that President Mahmoud Abbas will be similarly prepared to make the difficult decisions that achieving an agreement will require,” the letter said.

Among the signatories were some of Israel’s most stalwart supporters in recent Congresses and governments, including Sen. Joseph Lieberman (I-Conn.) who retired last year.