In an overwhelming show of bipartisan support, 363 members of the House signed on to a letter authored by Reps. Jesse Jackson, Jr. (D-IL) and Mike Pence (R-IN) to President Barack Obama pressing for tough and decisive measures to confront the threat posed by the Islamic Republic of Iran’s nuclear weapons program.

The letter, authored by the “proud progressive” and the “consistent conservative,” calls on the President to join with allies to “immediately impose crippling sanctions on Iran.” Those sanctions would ideally impact Iran’s Revolutionary Guard Corps, financial system, and the nation’s ability to import or refine petroleum. These sanctions, Jackson and Pence argue, would severely damage Iran’s economy and force the regime to reassess their nuclear program.

While all of the co-signers were clear about their desire to implement sanctions with teeth, there was less clarity on how to go about convincing key Iranian trade partners to join onto any meaningful resolution. “All of us would welcome international consensus,” said House Minority Whip Eric Cantor (R-VA), a co-signer of the letter, “But we all know the difficulties that we have had in bringing along both China and Russia, in particular, on this issue.” Both China and Russia hold veto power in the United Nations Security Council, and could significantly weaken any proposed sanctions.

While House members expressed confidence that the UN Security Council would be able to pass meaningful sanctions against Iran, they said Congress would move ahead with sanctions legislation in the coming days.