WASHINGTON (JTA) — Former Secretary of State Hillary Rodham Clinton said she was opposed to new Iran sanctions and urged Congress to give negotiations space to succeed.

“As President Obama has said, we must give diplomacy a chance to succeed, while keeping all options on the table,” Clinton said in a letter solicited by Sen. Carl Levin (D-Mich.), the chairman of the Senate Armed Forces Committee and a preeminent opponent of new sanctions under consideration in Congress.

“The U.S. intelligence community has assessed that imposing new unilateral sanctions now ‘would undermine the prospects for a comprehensive nuclear agreement with Iran’,” she said in the Jan. 26 letter released Sunday by Levin’s office. “I share that view.”

The statement by Clinton, until a year ago the secretary of state and before that a senator from New York and also first lady, is significant because she is potentially a presidential candidate in the 2016 elections and – like Levin – is seen as among the Democrats closest to the pro-Israel community.

The American Jewish Congress, led by Jack Rosen, a major donor to past presidential campaigns, is hosting a dinner in Clinton’s honor next month in New York.

Sens. Robert Menendez (D-N.J.) and Mark Kirk (R-Ill.) proposed the new sanctions, which have received vigorous support from much of the pro-Israel community, notably the American Israel Public Affairs Committee.

Introduced in December, the bill at first drew substantial Democratic support, but it has waned in recent weeks.

Proponents of the sanctions say they would strengthen the West’s hands in the talks with Iran.

New congressional sanctions, Clinton said, would collapse the international alliance that brought Iran to talks underway with the major powers aimed at stopping Iran from obtaining a nuclear weapon. Obama opposes the new sanctions and has said he would veto them.

Levin thanked Clinton for her letter in a statement on his website.

“It makes clear Secretary Clinton’s belief that tough sanctions helped bring Iran to the negotiating table, and that Congress and the administration are poised to act if Iran violates its commitments or fails to negotiate in good faith toward a final agreement,” he said. “Her letter is another strong signal to Congress that we should not take any legislative action at this time that would damage international unity or play into the hands of hard-liners in Iran who oppose negotiations.”