Late Monday, a political firestorm erupted after Republican Senators sent an open letter to leaders in Iran that challenged the ability of President Barack Obama to enter into a permanent deal regarding the nuclear program in Tehran.

U.S. Vice President Joseph Biden has denounced strongly the letter saying it offends him as a matter of principle and that it was beneath the dignity of an institution he revered.

Biden added that in his 36 years as a Senator, he could not recall another instance where senators wrote directly to another country and much less, one that has been a longtime adversary, stating the president did not have authority to reach an understanding with them.

Senator Tom Cotton a Republican from Arkansas signed the letter and he and 46 colleagues warned the government of Iran that a nuclear deal needed the approval of congress to last beyond the term of the current president.

The letter also said they hope the content of the letter enriches Iran’s knowledge of the U.S. constitutional system.

Iran on its website for foreign affairs dismissed the letter from the GOP as a propaganda ploy.

A top diplomat for Iran also said that it was strange that while the negotiations were still going on and no agreement was reached yet, some groups in U.S. politics are afraid of the possibility of an agreement and must resort to unconventional methods that are unprecedented in the history of diplomacy.

Obama compared the Republican Senators to the reactionary members of the government of Iran saying he thought it ironic that some members of the U.S. Congress want to find a common cause with Iran hardliners, which would make an unusual coalition.

The Senate minority leader Harry Reid said that Republicans only know how to make juvenile political attacks against President Obama. Another Democrat in Congress, Jared Polis a member of the House from Colorado called Cotton Tehran Tom.

John McCain the Republican Senator from Arizona said the Democrats could be protesting the letter to Iran as a form of diversion from what he called a lousy deal.

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