The Democratic chairman of the Senate Foreign Relations Committee accused the Obama administration Wednesday of using "fear-mongering" rhetoric in urging Congress to delay new sanctions against Iran as world powers try to secure nuclear concessions from Tehran.

Sen. Robert Menendez of New Jersey said he would continue to push for fresh sanctions in the wake of a nuclear deal brokered in Geneva, in which Iran agrees to a six-month pause in its nuclear program in exchange for eased sanctions worth $7 billion.

Menendez, speaking on the National Public Radio program "All Things Considered," cited White House Press Secretary Jay Carney's remarks at a recent press briefing about Americans not wanting a "march to war" with Iran as over-the-top rhetoric.

"What I don't appreciate is when I hear remarks out of the White House spokesman that ... if we're pursuing sanctions we're marching the country off to war. I think that's way over the top, I think that's fear-mongering," Menendez said, according to Reuters.

Many in Congress are skeptical, if not outright hostile, to the deal reached in Geneva. Menendez and Sen. Mark Kirk, R-Ill., are working on on legislation to reinstate the full force of sanctions and impose new ones if Iran doesn't make good on its pledge to roll back its nuclear program.

"We have to worry about the hardliners in Iran," Menendez said Wednesday. "And it seems that the Iranians get to play good cop-bad cop, (Iranian President Hassan) Rouhani as the good cop, the hardliners as the bad cop."

Menendez and Kirk hope to have their bill ready for other lawmakers to consider when the Senate returns Dec. 9 from its two-week recess, according to legislative aides.

The measure would require the administration to certify every 30 days that Iran is adhering to the terms of the six-month interim agreement and that it hasn't been involved in any act of terrorism against the United States.

Without that certification, sanctions worth more than $1 billion a month would be re-imposed and new sanctions would be added. The new penalties would include bans on investing in Iran's engineering, mining and construction industries and a global boycott of Iranian oil by 2015. Foreign companies and banks violating the sanctions would be barred from doing business in the United States.

The senators want to send the bill to the president before the end of the year, said the aides, who spoke on condition of anonymity because they weren't authorized to speak by name on the matter. White House officials wouldn't say if Obama might veto such legislation.

Secretary of State John Kerry, who delivered a video message to legislators this week urging them not to introduce new economic sanctions, spoke privately by telephone with Menendez in an effort to sway him, officials said. He reportedly warned of dire consequences.

Sanctions are as much about securing international cooperation as drafting tough laws. If major commercial powers that maintain business with Iran such as China or Japan, for example, decide to ignore the new restrictions, the Obama administration would have relatively few enforcement options. Shutting Chinese or Japanese banks out of the U.S. market isn't realistic because of the economic impact such a step would entail.

Having voted new sanctions against Iran four months ago, the House is waiting for the Senate to act. The House would probably overwhelming support any new legislation against Iran, given that it voted 400-20 in favor of new penalties in July.

Senate Majority Leader Harry Reid, D-Nev., has yet to determine how he'll react to the agreement, Democratic aides said.

The Associated Press and Reuters contributed to this report.