Forty-six Republican Senators signed a March 9 letter written by Sen. Tom Cotton (R-Ark.) to the government of Iran stating any agreement on the country’s nuclear program could end with the arrival of a new US President. The unusual open letter inserted Congress directly into the multi-party talks and drew scathing criticism from the White House for interfering in negotiations with a foreign power. The letter declares any deal not approved by Congress would be “nothing more than an executive agreement” between President Obama and Iranian Supreme Leader Ali Khameni, adding that a future US President could revoke the agreement or Congress could “modify the terms ... at any time.” White House officials and congressional Democrats blasted the letter as a partisan stunt that could have dangerous effects. Vice President Joe Biden, in a statement, declared that in 36 years in the Senate he never saw another instance “in which Senators wrote directly to advise another country—much less a long-time foreign adversary—that the President does not have the constitutional authority to reach a meaningful understanding with them.” Biden said the letter is “as false as it is dangerous,” and threatens the ability of the President to “negotiate with other nations on behalf of the United States.” Iranian Foreign Minister Javad Zarif called the letter “propaganda,” noting that per international law and precedent in inter-state relations, a change of Administration “does not in any way relieve the next Administration from international obligations undertaken by its predecessor.”