Paul said Friday that “proof of compliance and proof of goodwill” must be established before any sanctions are removed.

Secretary of State John F. Kerry and his team are working to finalize a deal by a June 30 deadline.

Paul said Friday the support for negotiations is where “I differ from some Republicans,” and said he doesn’t think they need to be immediately stopped.

“I think they need to keep the sanctions in place but I think keeping the door open, continuing conversations, is better than war,” he said.