Senate Foreign Affairs Committee Chairman Bob MenendezRobert (Bob) MenendezCongress must provide flexible funding for owners of repeatedly flooded properties Senate ethics panel resumes Menendez probe after judge declares mistrial Judge declares mistrial in Menendez bribery case MORE (D-N.J.) said Thursday that he is “very concerned” that Iran could develop a nuclear weapon before the Senate could pass more sanctions if President Obama’s negotiations fail.

"If we don't have a deal, I don't think we'll have the time to pass sanctions legislation before Iran could develop a nuclear weapon," Menendez said.

Menendez is one of 59 co-sponsors to a bill that would place new sanctions on Iran if it reneges on the interim nuclear deal or fails to reach a final deal that meets the Senate's demands. Obama has vowed to veto the bill, saying it would derail negotiations currently underway.

Menendez said the United States needs an "insurance policy" such as his legislation. 

“I am very concerned,” Menendez said on the Senate floor. “The real question is whether [the interim agreement] is a good enough deal.”

Menendez stopped short of joining a group of Republican senators who sent a letter to Senate Majority Leader Harry Reid (D-Nev.) Wednesday demanding that he immediately hold a vote on the sanctions bill. Menendez said he thinks national security should remain a bipartisan issue.

"I hope that we will not find ourselves in a partisan process trying to force a vote on a national security matter before its appropriate time," Menendez said. 

Menendez said he supports the administration’s negotiation efforts and doesn’t think it’s the right time to vote on the sanctions bill, but added that he was concerned that the deal wasn’t the “safeguard we need” to ensure Iran doesn’t develop a nuclear weapon.

“Any final deal must require Iran to dismantle large portions of its illicit nuclear program,” Menendez said. “We should insist on a long-term, 20-year verification program. ... Anything else will leave Iran on the cusp of being a nuclear power while rebuilding its economy.”

As part of negotiations, the administration lifted some sanctions in exchange for the Iran limiting its nuclear production. But Menendez said the current limitations still allow Iran to pick up nuclear productions shortly after negotiations end.

“We need a policy that guarantees Iran does not obtain nuclear weapons capability, period,” Menendez said. “Iran is simply agreeing to lock the door on their nuclear options. ... Once negotiations are over, they can simply unlock the door — sounds a lot like North Korea.”

Menendez said he was upset that the action plan agreed to only requires Iran to “take steps” to dismantle reactors, rather than actually dismantling them before sanctions are lifted.

The administration criticized those calling for more sanctions as “warmongers.” Menendez took offense to that, being that he opposed the wars in Iraq and Afghanistan, and said, “name calling is not an argument.”

“We will not be a scapegoat for a bad deal," Menendez said. "I want diplomacy to work ... but at a minimum we need to send a message to Iran that our patients is not unlimited."

He said sanctions were something to be used to keep the peace and prevent the need for war.

This article was updated at 6:30 p.m.