By Carlo Muñoz - 08/05/13 04:39 PM EDT
Seventy-six senators on Monday signed a letter demanding the Obama administration take a harder line to stop Iran’s nuclear program, including weighing possible military options.
The letter is signed by conservative lawmakers including Sens. Ted Cruz (R-Texas), Marco Rubio (R-Fla.) and Kelly Ayotte (R-N.H.), as well as prominent Democrats including Sens. Charles Schumer (N.Y.), Kirsten Gillibrand (N.Y.) and Barbara Mikulski (Md.).
Lawmakers called on President Obama to "bring a renewed sense of urgency to the process.”
"Iran needs to understand that the time for diplomacy is nearing its end," they said.
The letter comes as Hassan Rouhani was sworn in as Iran’s new president over the weekend. The White House on Sunday said the U.S. was willing to work with Iran, if the new leader engaged “substantively and seriously” on nuclear issues.
Congress, though, is working to enact tougher sanctions, with the House approving legislation last week to tighten controls against Iran's energy, shipping and insurance sectors.
Schumer last week said military action against Iran should never be taken off the table, but backed tightening sanctions as the preferred method to stop the country’s nuclear development.
“Ratcheting up the economic pressure against Iran is imperative,” he said last Wednesday on the Senate floor, “so that Iran sees it’s not in their best interests economically to continue on this path.”
The Pentagon has already drafted up plans for possible military action against Tehran, should the administration's strategy fail to stop Iran's nuclear program.
However, Defense Department leaders continue to back the White House's approach of diplomatic and economic pressure to bring Tehran to heel.
Iran’s regime insists its nuclear enrichment efforts are geared toward energy development, and not weaponization.
Washington and its allies argue the Iranian program clearly puts the country on the path to developing nuclear arms.