Senator Ted Cruz has criticised Vice President JD Vance's negotiation of a memorandum of understanding with Iran, calling it "a terrible deal," as he signals interest in a possible 2028 presidential run. Cruz, who lost the 2016 Republican nomination to Donald Trump, has also said the party has not yet united behind Vance as its heir apparent, suggesting there would be a broader debate within the GOP about its future direction. The remarks matter because they expose early cracks in Republican unity over succession planning, with several senior figures positioning themselves ahead of the next primary race.

Cruz has been touring Iowa, an early primary state, gauging support for a potential campaign, and is separately promoting a new book about Supreme Court Justice Clarence Thomas. He has also criticised Vance's continued friendship with broadcaster Tucker Carlson amid antisemitism allegations against him. Vance, asked about Cruz's ambitions during a White House briefing, called him "authentic and likable" but urged Republicans to focus on the midterms rather than 2028, while allies dismissed Cruz as no serious threat. Secretary of State Marco Rubio, also seen as a contender, has said he would not run if Vance does, and Trump himself has remained noncommittal about backing Vance, saying it is "way too early" to weigh in.