Hugh Grant thinks affairs can be good for a marriage.

Explaining how he "likes" the fact his 'Florence Foster Jenkins' character has a mistress, he added: "I always admire the French and the Italians who are very devoted to their marriages.

"They take them extremely seriously, but it is understood that there might be other visitors at 5 o'clock in the afternoon. You just never boast about. They never say anything, but that's what keeps marriages together."

The 55-year-old actor - who was infamously arrested in 1995 after being caught with a prostitute while still in a relationship with Elizabeth Hurley - branded marriage "unromantic" and doesn't believe in the institution because he doesn't think human beings are meant to be faithful to just one person.

He told Sirius XM DJ Howard Stern: "I can see the lovely aspect if you marry exactly the right person - your best friend and it's cozy and it's lovely. But, people make so many mistakes.

"Do I think human beings are meant to be in 40-year-long monogamous, faithful, relationships? No, No, No. Whoever said they were? Only the bible or something. No one ever said that was a good idea.

"I think there's something unromantic about marriage. You're closing yourself off."

Hugh - who has children Tabitha, four, and Felix, three, with Tinglan Hong, and John, three, and an eight-month-old daughter, with Anna Eberstein - also admitted to being "patronising" towards his 'Florence Foster Jenkins' co-star

Simon Helberg because it was his first movie, but quickly realised the 'Big Bang Theory' actor was, in fact, a "much bigger star" than he is.

He admitted: "This guy Simon Helberg who's in 'Florence Foster Jenkins', I might have been vaguely patronising to him because he hadn't done films before.

"Gradually, you realise, not only is the guy a much bigger star than me, he's maybe the richest man I've ever met."