Former Texas Congressman Ron Paul on Saturday cast skepticism on the motives of senators who want a congressional review of President Barack Obama's emerging nuclear deal with Iran — a group that includes his son, a newly minted presidential candidate.

"I think the Congress has a point — whatever you agree to, we want to review it — but I strongly disagree with the motivation of that statement made by so many members of Congress, especially in the Senate," Paul said during a speech at a Libertarian conference at the University of Texas at Austin.

"'We have this constitutional responsibility to review this agreement,'" Paul added in a mocking tone. "What a joke that is. That's not reasonable. They're out to stop peace. They're terrified that peace might break out."

Paul's son, Kentucky Sen. Rand Paul, is cosponsor of the Iran Nuclear Agreement Review Act of 2015, which would require the Obama administration to "submit the text of any agreement to Congress," according to his office. Rand Paul launched his 2016 presidential campaign last week.

Asked after the speech if his son was among the senators whose motives he was skeptical of, Ron Paul said he was not doing any interviews.

Rand Paul is among the dozens of senators who signed a letter to Iranian officials in an effort to push for a greater role for Congress in the nuclear negotiations. Paul has said he added his signature because he believes in the separation of powers.

The father-son relationship has been under the microscope as Rand Paul sets out on his 2016 presidential run. The son has faced questions about how much he plans to embrace his father's famous libertarianism as he seeks to grow the GOP's ranks and capture the White House.

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