A hawkish Republican senator has expressed doubts about the feasibility of Donald Trump's idea of clinching a verifiable nuclear deal with Tehran, arguing that such a deal would not be possible as Iran's leaders are not trustworthy.

"In my humble opinion, there is no such thing as a verifiable nuclear peace agreement with the Iranian Regime, who are religious Nazis," Republican Senator Lindsey Graham, a close Trump ally, said on Wednesday.

"The ayatollah and his henchmen are not trustworthy on the nuclear front," the hawkish senator from South Carolina said in a post on his X account.

Earlier in the day, Trump said he "would much prefer a Verified Nuclear Peace Agreement, which will let Iran peacefully grow and prosper."

"We should start working on it immediately, and have a big Middle East Celebration when it is signed and completed. God Bless the Middle East!" he said in the post on his Truth Social platform.

Graham, however, said the Islamic Republic's "ambitions to obtain a nuclear weapon are crystal clear based on decades of lies and deceit. When the Iranian Regime says death to Israel and America, they mean it."

Iran has denied seeking a nuclear weapon, but Israel has long contended Tehran wants a bomb and that its arch-enemy poses an existential threat.