Angelina Jolie has been warned she is in danger of losing primary custody of her six children to estranged husband Brad Pitt.

Court documents show a judge has restricted how much Jolie can control Pitt’s interaction with the kids, according to reports by outlets including People and TMZ.

As reported originally by The Blast, Pitt has also been given unrestricted phone access to his children.

The latest twist brings new heat to the ongoing custody battle, which began when Jolie filed suddenly for divorce from Pitt in September 2016.

Since then, Maddox, 16, Pax, 14, Zahara, 13, Shiloh, 12, and twins Vivienne and Knox, 9, have lived with their mother.

Pitt has had only restricted, supervised access to his family.

At the time of the breakup, he was investigated and cleared by authorities over abuse allegations relating to an incident on a private jet.

But now the Oscar winner has been told to take steps to improve the children’s relationship with their father, according to the documents.

A judge in the former couple’s case believes the children “not having a relationship with their father is harmful to them”.

The judge said it was “critical” all the children had a “healthy and strong relationship” with both parents, and that Jolie must let Pitt repair and maintain his bond with them.

If the children “remain closed down” to their father, the time they spend with their mother could be cut, the judge said in the court documents.

It may even “result in the court ordering primary physical custody” to Pitt.

Reps for Jolie, 43, and Pitt, 54, are yet to respond to media requests for comment.

Brad Pitt, Jolie and their family arrive in Japan in November 2011. Photo: Getty

The actor told GQ magazine in May 2017 that custody battles are “an investment in vitriolic hatred” and said hardly seeing his children had taken a toll: “It’s just very, very jarring for the kids, to suddenly have their family ripped apart.”

Jolie has reportedly been given a parenting blueprint by the judge, including asking her to give Pitt each child’s mobile phone numbers so he can call anytime.

The Maleficent star is not to read any text messages between the children and their father, or secretly monitor calls.

The court also outlined a new custody schedule for the children for the northern summer.

Last week Pitt started spending four hours a day with one or two of the kids at a time in London, where they are living in a rented house while their mother films Maleficent 2.

Jolie can’t be present during the visits, but a child psychologist will be.

In late June, Pitt’s access ramps up to 10 hours a day. From early to mid-July, he’ll have the kids for four consecutive days, and in late July they’ll stay with him in Los Angeles for about a week.

When the kids are staying with their dad, Jolie can only call them once a day at a prearranged time.

For now, Pitt is travelling back and forwards from London, where the children are doing school work in a trailer on the movie set.

Because he’s 16, Maddox gets to decide how much time he wants to spend with his father.

In his GQ interview, Pitt said he let his work “take me away” to the detriment of his family.

“Kids are so delicate. They absorb everything. They need to have their hand held and things explained. They need to be listened to. I want to be better at that.”