Kate Winslet has said she refused a director’s offer to edit a sex scene in which she showed a “bulgy bit of belly” for her latest television series.

The actor claimed Craig Zobel, the director of her new HBO series Mare of Easttown, had offered to show her body in a more flattering light.

Winslet, who plays detective and a grandmother Mare Sheehan in a Pennsylvania town in the programme, the finale of which was broadcast in the UK on Monday, said she had refused and told Zobel: “Don’t you dare.”

She also said she twice sent back the promotional poster for the drama because she felt it had been altered too much.

“I’m like: ‘Guys, I know how many lines I have by the side of my eye, please put them all back,’” Winslet, 45, told the New York Times.

“I said to my husband [Edward Abel Smith]: ‘Am I OK with that? Is it all right that I’m playing a middle-aged woman who is a grandmother who does really make a habit of having one-night stands?’ He’s like: ‘Kate, it’s great.’”

The actor added: “Listen, I hope that in playing Mare as a middle-aged woman – I will be 46 in October – I guess that’s why people have connected with this character in the way that they have done because there are clearly no filters.

“She’s a fully functioning, flawed woman with a body and a face that moves in a way that is synonymous with her age and her life and where she comes from. I think we’re starved of that a bit.”

Winslet said, however, that she may not be “comfortable” with doing another nude scene.

“It’s not even really an age thing, actually,” she said. “There comes a point where people are going to go: ‘Oh, here she goes again.’”

In an interview with the Guardian in February, Winslet said she had been forced to respond to derogatory comments about her weight from a young age.

“In my 20s, people would talk about my weight a lot. And I would be called to comment on my physical self. Well, then I got this label of being ballsy and outspoken. No, I was just defending myself.”

The actor said she had revisited some newspaper articles written about her in the late 1990s from when she was 19 “and it was almost laughable how shocking, how critical, how straight-up cruel tabloid journalists were to me”.

In January, Keira Knightley said she would no longer agree to shoot intimate scenes if the film was directed by a man.

The actor, who credited the “male gaze” and her own personal vanity with the decision, said: “If I was making a story that was about that journey of motherhood and body acceptance, I feel like, I’m sorry, but that would have to be with a female film-maker.

“I don’t have an absolute ban, but I kind of do with men.”