Iran's parliament is gearing up to retaliate against any move by Congress in the new year to pass additional sanctions against Tehran.

More than a third of Iran's legislative body has signed on to a bill that would ignore a six-month interim agreement with the U.S. and accelerate the country's nuclear development if Congress passes a new round of sanctions.

Signed by more than 100 members of Ian's parliament, the measure would call for an increase in uranium enrichment to 60-percent purity from the current levels of 20 percent. Contrary to the deal with the U.S., it would also require the reactivation of the partially built Arak heavy-water nuclear reactor.

The lawmakers backing the bill presented it to parliament's leadership, which could give it the green light or move to block it from coming to a full vote.

Mehdi Moussavinejad, a member of the parliament's energy committee, told an Arab news outlet that the bill would speed up the development of the nation's nuclear program if new sanctions are imposed or if existing sanctions are intensified.

The move came just two weeks after Iran threatened to pull out of negotiations in protest of U.S. enforcement of existing sanctions against Tehran. Iran's Foreign Minister Mohammad Javad Zarif said he felt “blindsided” by a U.S. announcement in mid-December that it was targeting a dozen companies and individuals it says evaded current sanctions.

After reassessing the status of the agreement with the U.S., two days later Zarif said the Iranians had decided to move forward with the deal and are “committed” to its implementation.

“The process has been derailed. The process has not died,” he told CBS News at the time. “We are trying to put it back and to corrected the path and continue the negotiations because I believe there is a lot at stake for everybody.”

Hardliners in Congress pushing for additional sanctions say Iran is bluffing and cannot risk another round of sanctions by reneging on the agreement because the economic pressure would be too great.

But the legislation was an indisputable sign of the ongoing tensions between the two sides after last month's historic agreement between the United States, five other world powers and Iran to freeze aspects of the Tehran's nuclear program.

Senate Banking Committee Chairman Tim Johnson, D-S.D., last week announced that he would hold off on pushing a new sanctions measure through his panel after Secretary of State John Kerry said the bill would jeopardize the deal with Iran.

Still, 26 senators have signed on to a new sanctions measure they said they would pursue if Iran fails to comply with the agreement's requirements.

Iranian Deputy Foreign Minister Abbas Araqchi said Wednesday the two sides were still haggling over the finer points of the deal and continued divisions on some key points could hamstring the process.

He told Fars new agency that “no new sanctions will be accepted and any news sanctions will kill negotiations.”

“Since we have witnessed the lack of trust on the part of the other side in the past, we cannot be quite sure about their commitment,” he said.