The UN Security Council may lift sanctions against Iran once a nuclear deal is struck, preventing the US from rejecting or later repealing the agreement.

The United Nations Security Council may consider lifting sanctions on Iran after a nuclear agreement is reached in order to prevent the United States from undermining the deal, according to a report by Reuters. Secretary of State John Kerry noted to the Congress on Wednesday that such an agreement is not legally binding, meaning that future presidents could choose not to implement it. That point was raised again in a letter by 47 Republican senators to Iranian leaders.

An anonymous western official told the news agency that those officials involved in the negotiations would consider a draft resolution for the UN Security Council to begin removing international sanctions.

“If there’s a nuclear deal, and that’s still a big ‘if’, we’ll want to move quickly on the U.N. sanctions issue.” The negotiations between Iran and the P5+1 have mostly focused on US and EU sanctions against Iran’s energy and financial sectors.

Anonymous US officials confirmed the information to Reuters, noting that the P5 in the P5+1 referred to the five permanent members of the UN Security Council, and any resulting nuclear agreement would therefore receive UN support. “There is an interesting question about whether, if the Security Council endorses the deal, that stops Congress undermining the deal,” a Western diplomat said.

There are currently eight UN resolutions against Iran’s nuclear program, including four imposing sanctions. The resolutions ban uranium enrichment, and prohibit Iran from buying or selling nuclear technology and ballistics missile parts.

The US Constitution gives the President the responsibility for negotiating treaties, but grants the Senate power to reject treaties. It also allows the Congress to repeal treaties, even if the US is still considered obligated to follow the treaty under international law. This has led to the concern that, even if the P5+1 and Iran reach an agreement on the latter’s nuclear program, future US governments would not uphold the agreement. The repealing of UN sanctions would, however, be binding on the US and make it much more difficult to reinstitute the sanctions regime against Iran.