Actor George Clooney has taken aim at the Trump administration with an insult that would require reaching for the dictionary.

Clooney delivered a blistering assessment of the US president and his cronies at the Venice Film Festival where he is receiving a lifetime achievement award.

When asked about the current state of his country, Clooney said it was being run by a “kakistocracy” which he explained was “a country run by the least qualified people”.

“I think maybe we have a kakistocracy right now, but we’ll get through it,” he said.

The online dictionary specifically defines kakistocracies as “government by the worst persons; a form of government in which the worst persons are in power”.

The 65-year-old Democrat also singled out Defence Secretary Pete Hegseth as an example of the regime embracing “cruelty” in public life.

“You see what the Secretary of Defence just tweeted out a picture about women from the military in Canada and you’re going, what’s wrong with you?” he told journalists.

“There’s the sense of decency in all of these and I’m ashamed of all that, but we will get through it and we will come out better on the other side.”

Despite the the US being at an “unfortunate” moment in time, Clooney said he was “optimistic” about the future.

The outspoken political activist said he had lived through rough periods in the country’s history such as widespread unrest in 1968.

“We lost Martin Luther King and Bobby Kennedy in the same year. There was tons of violence. The Capitol was surrounded with tanks,” he said.

“We’ve had some other difficult times, but this is one of them.”

He said “with any luck” the 2028 presidential election would restore some “normalcy”.

Clooeny is being honoured with the Golden Lion for Lifetime Achievement at the opening ceremony in Venice on Wednesday night (local time).

Actress Laura Dern will deliver the tribute. The two appeared together in Jay Kelly, which premiered in Venice last year.

Danny Boyle’s Ink has been selected as the festival’s opening film.

The film tells the story of how Rupert Murdoch and Larry Lamb transformed The Sun into a powerhouse of British tabloid journalism. It is one of 21 films competing for the festival’s top prize, the Golden Lion.

Among the most eagerly awaited films is the premiere Primetime, starring Robert Pattinson as real-life journalist Chris Hansen.

Hansen’s NBC series To Catch a Predator used hidden cameras to confront suspected sex offenders, turning the encounters into controversial television.

Penélope Cruz and Javier Bardem, meanwhile, play a married couple in Bunker, about an architect commissioned by a tech billionaire to build an underground refuge to ride out doomsday.

Over the festival’s 11 days Liam and Noel Gallagher are also expected for the premiere of Oasis reunion documentary Don’t Look Back in Anger.

The Gaza war will also feature prominently, with Naza, from two of the filmmakers behind the Oscar-winning No Other Land, screening at the festival.

-with AAP