Freshman Republican Sen. Tom Cotton (Ark.) says he has no regrets about spearheading a letter to Iran’s leaders warning any nuclear deal negotiated with international powers could be revoked in two years.

{mosads}The Obama administration and Democratic leaders have pummeled Cotton for interfering in international security talks, ignoring a precedent of stopping partisan politics at the water’s edge.

Cotton told CBS’s “Face the Nation” Sunday that he has “no regrets at all” and accused President Obama of “not negotiating for the hardest deal possible.”

He argued that, if Obama and Secretary of State John Kerry are trying to negotiate the toughest possible deal, they would be glad to point to Cotton’s letter — which 46 other Senate Republicans signed — to gain leverage in the talks.

He said he wrote the letter because “Iran’s leaders needed to hear the message loud and clear.”

He argued that Iran’s foreign minister, Javad Zarif, indicated he did not fully understand U.S. constitutional law by urging the Obama administration to go straight to the United Nations to finalize a nuclear agreement, bypassing Congress.

“He thinks that international law can override our constitutional system,” Cotton said.

In an interview with CBS aired earlier on the same program, Secretary of State John Kerry slammed Cotton’s letter as an “unprecedented” and “calculated” attempt to interfere with negotiations.

Former Secretary of State Madeleine Albright called Cotton’s action “outrageous” and compared it to a hypothetical scenario of lawmakers sending a letter to Soviet leader Nikita Khrushchev to undermine President Kennedy during the Cuban missile crisis.

Cotton dismissed both critiques.

He said Kerry’s comments to CBS appeared to backtrack from his testimony before the Senate Foreign Relations Committee last week.

“I’m surprised by Secretary Kerry’s comments this morning because just a few days ago he testified before the Senate to say any deal would not be legally binding,” Cotton said. “And now he says that future Congresses cannot change a mere executive agreement if we disagree with them or if a future president disagrees with them?”

He said Albright, while the nation’s top diplomat during the Clinton administration, entered into a “fundamentally flawed” nuclear agreement with North Korea.

“They almost immediately started cheating on it, and a near 12 years later they detonated their first nuclear weapon. Now the world has to live with the consequences of a nuclear North Korea,” he said.