Story highlights A Republican senator is drafting legislation to allow Congress to vote on negotiations with Iran

The White House sent a letter saying it would further threaten talks over Tehran's nuclear program

Washington (CNN) In a strongly worded letter, the White House Saturday told Senate Foreign Relations Chairman Bob Corker (R-TN) a bill he is drafting would likely have a "profoundly negative impact" on the ongoing negotiations between the U.S. and Iran over Tehran's nuclear program.

Corker is working on legislation that would force the Obama Administration to submit any deal reached with Iran for a vote by Congress. The White House earlier threatened to veto such a measure.

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White House Chief of Staff Denis McDonough, in the three page letter released publicly Saturday evening, told Corker his legislation could be detrimental to the talks with Iran by "emboldening Iranian hard-liners, inviting a counter-productive response from the Iranian majiles (Majles, the Parliament); differentiating the U.S. position from our allies in the negotiations; and once again calling into question our ability to negotiate this deal."

As the U.S. and Iran prepare for the next round of negotiations this coming week, there has been a growing debate between Republicans on Capitol Hill and the Obama Administration about how much authority Congress has regarding the fate of the agreement.

White House Chief of Staff Denis McDonough

"The legislation you have introduced in the Senate goes well beyond ensuring that Congress has a role to play in any deal with Iran. Instead, the legislation would potentially prevent any deal from succeeding by suggesting that Congress must vote to 'approve' any deal and by removing existing sanctions waiver authorities that have already been granted to the President," McDonough wrote.

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