A bipartisan group of senators wrote to Trump administration officials on Wednesday urging them to declassify two side letters related to the U.S.-Saudi nuclear deal — written agreements related to the deal that are not part of the text of the deal itself. Congress is currently reviewing the agreement, as mandated by law.

The group notably includes two Republicans: Sens. Rand Paul (R-KY), who has frequently found himself at odds with President Donald Trump, and Sen. John Kennedy (R-LA), generally a Trump supporter who nonetheless has expressed reservations about the nuclear deal, which could allow for nuclear enrichment on Saudi soil.

The letter was led by Sens. Jeff Merkley (D-OR) and Ed Markey (D-MA). It was co-signed by Sens. Chuck Schumer (D-NY), Jeanne Shaheen (D-NH), Jack Reed (D-RI), Patty Murray (D-WA), Sheldon Whitehouse (D-RI), Bernie Sanders (I-VT), Chris Van Hollen (D-MD), Elizabeth Warren (D-MA), Tim Kaine (D-VA), Adam Schiff (D-CA), Kirsten Gillibrand (D-NY), Michael Bennet (D-CO), Ron Wyden (D-OR) and Peter Welch (D-VT).

The letter, addressed to Secretary of State Marco Rubio and Energy Secretary Chris Wright, notes that the side letters have never before been classified for any previous foreign nuclear deal: “We are aware of no precedent for classifying and withholding the side letters, particularly when the stated purpose is peaceful nuclear cooperation.”

The lawmakers said that Congress and the public must have “access to the full text” of the deal in order to gain a “clear understanding of the commitments being made on the nation’s behalf and those being made by Saudi Arabia to the United States. The side letters affect the obligations and operations of the underlying agreement and cannot be viewed in isolation from it.”