Fifty Senate Republicans wrote to the foreign ministers of the U.K., France and Germany on Tuesday urging them to hold firm in triggering snapback sanctions on Iran and requesting their cooperation in sanctions enforcement.

“While we back diplomatic efforts to restore Iran’s compliance with its International Atomic Energy Agency (IAEA) commitments, the international community should not allow hollow gestures and cynical threats from Tehran to stop the snapback process,” the lawmakers wrote in a letter obtained by Jewish Insider. “The regime has abused diplomatic processes for years to avoid penalties. Sanctions relief should only be negotiated after snapback is fully implemented.”

They said that full, verifiable dismantlement of Iran’s nuclear program, restoration of International Atomic Energy Agency inspections and the end of Iran’s support for terrorist proxies and its ballistic missile program should be the “minimum” bar for sanctions relief.

The lawmakers, led by Senate Foreign Relations Committee Chairman Jim Risch (R-ID), said they want to work with the European allies to ensure all United Nations member states and private actors comply with the U.N. sanctions.

“We understand your governments’ hope that diplomacy would eventually succeed in ending Iran’s nuclear program, but after a decade of the regime’s intransigence, its repeated deceptions, and its open support for Putin’s war against Ukraine, we will count on your governments to lead the charge and advance a passionate enforcement of sanctions against Iran — whether at the European Union, in your respective capitals, or in foreign capitals,” the letter continues.

Every Senate Republican — except for Sens. Mike Lee (R-UT), Rand Paul (R-KY) and Tommy Tuberville (R-AL) — signed the letter.

The 50 signatories called on the European governments to work with the U.S. in joint efforts to prevent Iranian “proliferation and acquisition of military, missile, and nuclear goods, technologies, and components” and to “fully shutter Iran’s banking sector abroad,” including all bank branches in Europe.

“Closing off the regime’s financial pathways will curb the regime’s aggression. More pressure is necessary to ultimately bring Iran back to meaningful and serious diplomatic engagement on the full spectrum of its malign activities,” the lawmakers continued.

They also said they are “deeply concerned” about Iran’s oil sales to China and smuggling operations, and said they “appreciate the cooperation your governments have already shown in curbing these sales.”

The lawmakers thanked the E3 allies for triggering the snapback sanctions and their “leadership at this pivotal moment.”

An individual familiar with the situation told JI that Tuberville’s office was not provided with a deadline for signing on to the letter. The individual added that Tuberville has confidence in the Trump administration’s leadership on foreign policy.

Lee and Paul did not respond to requests for comment.