A top Democratic senator who has criticized the Biden administration for a number of policies again pushed back on Tuesday, warning against any attempts to remove the Islamic Revolutionary Guard Corps (IRGC) from the State Department’s Foreign Terrorist Organization list.

Senator Joe Manchin sent a letter to Secretary of State Antony Blinken requesting a detailed update on the status of the indirect nuclear discussions between the US and Iran.

“While I support President Biden’s commitment to reengaging the Government of Iran in diplomacy, we should not reward Iran with sanctions relief before they demonstrate verifiable efforts towards curbing their malign influence holistically,” Manchin said in his letter to Blinken.

The Biden administration reportedly considered removing the IRGC from the US terror blacklist. After public criticism and pushback from Biden’s own Democratic party, which has traditionally supported a deal with Iran, reports suggested that the administration was looking to de-list the IRGC-Quds Force.

As Putin wages war against Ukraine and threatens democracy in Europe, the U.S. cannot allow the IMF to be its piggy bank and finance these attacks. The Russia and Belarus SDR Exchange Prohibition Act would stop these funds from reaching Russia or Belarus. https://t.co/fSbp7nH0te

— Senator Joe Manchin (@Sen_JoeManchin) April 19, 2022

But on Monday, the State Department appeared to shoot down the Iranian demand. State Department Spokesman Ned Price said that if Tehran wanted to discuss sanctions outside of the original 2015 nuclear deal, it would need to address US concerns beyond the JCPOA.

Price was referring to Iran’s support for terrorist groups and its ballistic missile program, neither of which are addressed by the nuclear deal.

On Tuesday, Manchin said the idea of lifting the designation of the IRGC was being proposed to assist with the US energy crisis. “Let me be clear, the IRGC is a terrorist organization. We must not be shortsighted in the use of sanctions relief to mitigate our present energy challenges, Manchin said.

“Sanctions are our primary leverage to facilitate agreements on halting malign Iranian actions and should not be used to achieve non-strategic objectives,” he added.

The West Virginia senator said the Biden administration should continue investing in an “all-of-the-above domestic energy policy” to bolster US national security and help its allies and partners abroad. “We cannot and should not look to Iran to solve our energy problems.”

Manchin also slammed Iran’s leadership for funding terrorism in the Middle East and Africa for decades, “including the deaths of US service members.”

He said that he agreed with the Biden administration on the need to halt the progress of Iran’s nuclear weapons program. “However, we must continue to negotiate a halt to Iran’s use of state-sponsored terrorism, advancement of its missile program, and the continued proliferation of dual-use technologies,” Manchin said.

Much criticism was pointed at the Obama administration, which brokered the 2015 deal, for the weakness of the agreement and its failure to address Iran’s destabilizing behavior.

“I was disappointed in the outcome of the negotiations in 2015, and I will do everything in my power to ensure we do not repeat the mistakes of the past,” Manchin.

Other high-profile Democratic senators have voiced their objection to the current concessions being offered by the Biden administration’s negotiating team, which Rob Malley leads.

Bob Menendez, the Senate Foreign Relations Committee chairman, has been an outspoken critic of the now-defunct 2015 nuclear deal, which the Biden administration is adamant on reviving.