Arnold Schwarzenegger has spoken out about his role in his affair with his family's housekeeper. Photo / Getty Images

Arnold Schwarzenegger has opened up about the affair with his housekeeper that ended his marriage and resulted in a son born just days after he welcomed another son with his wife.

The body builder turned action hero turned governor said in a new interview with People magazine that his relationship with housekeeper Mildred Baena was “my f*** up” and led to the demise of his marriage with Maria Shriver in 2011.

“Remember it’s not like we had a feud,” he explained to the entertainment news outlet. “We didn’t have a fight.”

Schwarzenegger and Baena’s love child, Joseph, arrived five days after his son with Shriver, Christopher, was born.

He revealed even though it was his mistake that ended his marriage to Shriver, a journalist and member of the Kennedy family, he still has love for her.

“My chapter with Maria will continue on forever,” he said. “Even though it’s a different relationship, there’s no reason for me to feel anything other than love for her.”

The couple are parents to daughters Katherine, 33, and Christina, 32 and sons Patrick, 30 and Christopher, 26.

“We always made it very clear that the kids should not suffer because of [the affair],” he told People.

“And she has her things, her relationship, I have mine, but we always communicate about the kids, about the holidays, about birthday parties and Mother’s Day parties and Christmas,” says Schwarzenegger, who has been in a relationship with physical therapist Heather Milligan since 2013.

But when it comes to Joseph, a source has told Page Six he has never really been accepted by his half-siblings.

“Arnold has always treated [Joseph] like all his other kids — very fairly. But for whatever reason, the other kids take [the affair] out on Joe,” the source said.

In the Netflix documentary Arnold it was revealed Shriver learned about Schwarzenegger’s affair during a marriage counselling session in 2011.

The actor recalls the moment his infidelity came to light.

“[Maria] wants to know if you’re the father of Joseph,” he remembers the counsellor asking of the housekeeper’s child who bore a striking resemblance to her then-husband.

“I thought my heart stopped,” he says in the documentary. “And then I told the truth.”

Their marriage ended that year although according to Page Six their divorce wasn’t finalised until 2021 because the lack of a prenup was said to have made for a messy asset split.