Amanda Seyfried has a "familial" bond with Dominic Cooper.

The 40-year-old actress lives in the US, while her Mamma Mia! co-star lives in London with his girlfriend Gemma Chan - but Amanda insists that they remain close friends in spite of the distance.

The Hollywood star told People: "Our lives are very different.

"We live in very different places and I just have nothing but good feelings about him."

Amanda explained that their off-screen relationship has evolved over the years.

She said: "When you're with somebody for a long time when you're younger, it just kind of evolves into this familial, nice, soft kind of bond."

Amanda feels "really lucky" to have such a long-lasting friendship with Dominic, her co-star in Mamma Mia!, the 2008 musical-comedy film.

The actress said: "He's hilarious. It's funny, relationships, friendships, they always evolve. It's just so crazy that as we get older, you just want to be kind if you can. Especially if you had a friendship like that, I think it's amazing, and I feel really lucky."

Meanwhile, Amanda previously heaped praise on Sydney Sweeney, describing her co-star in The Housemaid as a "sweetheart".

The actress praised Sydney, 29, for how she's coped with the pressures of fame and success.

Amanda told Vanity Fair: "I don't envy anything she's going through.

"I've spent a lot of time with her; we just hit it off immediately. She's a sweetheart. She's a very generous, kind person at her core. I have to be honest: I did not have a moment like she's having ever.

"[My Mean Girls costar] Lindsay Lohan, we're buddies, and it's really, really, really harmful to people to have that kind of overnight spotlight. Because any press, good or bad, is still a blinding spotlight, and you have to maneuver and negotiate your way around it and outside of it. It's acrobatics that I don't think most people are capable of figuring it out at that age."

Amanda thinks a sudden rise to stardom can actually be "dangerous". However, the actress praised Sydney for how she's coped with the extra attention.

She said: "I actually admire the way Syd shows up for work. She always has a smile on her face, even if she's miserable. I hope it doesn't change."