Coalition of U.S. senators urge President Obama to endorse tougher sanctions on Iran

A coalition of 76 U.S. senators sent a bipartisan letter on Friday to President Barack Obama calling for tougher sanctions against Iran, the Senate Committee on Foreign Relations said on Monday.

Senators Bob Menendez (D-N.J.), Lindsey Graham (R-S.C.), Bob Casey (D-Pa.), Roy Blunt (R-Mo.), Tim Kaine (D-Va.) and Kelly Ayotte (R-N.H.) circulated the letter. The authors said the U.S. must tighten sanctions against Iran until it sees a slowdown of the country's nuclear activities.

"With the election of Hassan Rouhani, the Iranian people signaled their clear dissatisfaction with Iran's government and its policies," the authors said. "We hope such a surprising and convincing electoral outcome will persuade Supreme Leader Ayatollah Ali Khamenei to abandon Iran's nuclear weapons quest. But until we see a significant slowdown of Iran's nuclear activities, we believe our nation must toughen sanctions and reinforce the credibility of our option to use military force at the same time as we fully explore a diplomatic solution to our dispute with Iran."

The letter said the senators sympathized with the plight of the Iranian people, but said Iran used past negotiations to stall for time while moving closer to being able to rapidly produce weapons-grade uranium.

"Accordingly, Mr. President, we urge you to bring a renewed sense of urgency to the process," the authors said. "We need to understand quickly whether Tehran is at last ready to negotiate seriously. Iran needs to understand that the time for diplomacy is nearing its end. We implore you to demand immediate serious moves on Iran's part. Iran should move quickly toward compliance with United Nations Security Council resolutions demanding it suspend enrichment. Iran must cease installing centrifuges, agree to the removal of 20 percent enriched uranium from Iran, and cease work on the heavy water reactor being built in Arak."

The letter said the resolution of this matter is dependent on four strategic elements: a sincere demonstration of openness to negotiations, an explicit and continuing message that the U.S will not let Iran acquire nuclear weapons capability and a convincing threat of the use of force.

The senators closed by saying they will support the President in doing all he can to resolve the pressing challenge on an urgent basis.