Washington DC - Ted Cruz endured a torrid grilling by former Fox News host Tucker Carlson in an interview that highlighted the Florida senator's alarming views and ignorance on key topics.

The full two-hour conversation was released Wednesday, but teaser clips posted on X the day before had already gone viral by then.

Much of the interview was dominated by Israel's ongoing assault on Iran and the question of potential US involvement.

Cruz, a staunch ally of President Donald Trump and one of the loudest cheerleaders for war, was quickly put on the spot by Carlson, whose has been a prominent voice among those in Trump's coalition who oppose entanglements in overseas conflicts.

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In a painful exchange, Carlson asked Cruz to name the population of Iran, a country of over 90 millions people whose leader – Ayatollah Ali Khamenei – the Florida Republican wants to see toppled.

"I don't know the population at all. No, I don't know the population," an indignant Cruz responded, before dismissing the importance of the questions altogether: "Whether it's 90 million or 80 million or 100 million, why is it relevant?"

Carlson then moved on to the ethnic mix of Iran's population, which left Cruz spluttering vague answers before sarcastically conceding: "OK, I am not the Tucker Carlson expert on Iran."

There was plenty of time for more humiliating moments for Cruz, who at one point seemed to imply that the US was directly involved in Israel's unprovoked attack last Friday, before quickly clarifying that "we are not bombing (Iran)."

He also inexplicably denied that the American Israel Public Affairs Committee (AIPAC) is a group lobbying on behalf of a foreign government, before dropping a theological justification for unconditionally backing Israel, a state which stands accused of committing myriad war crimes and crimes against humanity in Gaza.

"Number one, because biblically, we are commanded to support Israel," Cruz insisted, though he was unable to identify Genesis as the source of the commandment.

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Over the course of the tense sit-down, both men repeatedly insulted and talked over each other, with Carlson at one point accusing his guest of acting in a "sleazy, feline way" by implying that he was antisemitic.

As Cruz was widely mocked online, Trump weighed in by posting: "Somebody please explain to kooky Tucker Carlson that IRAN CAN NOT HAVE A NUCLEAR WEAPON!"

There is widespread consensus, including among US intelligence agencies, that Iran was not pursuing nuclear weapons before Iran launched its unprecedented campaign.