TMZ: Brad Pitt Struggles to Maintain Relationship with Kids

Brad Pitt and Angelina Jolie are at war in their divorce case, but the more immediate struggle is the co-parenting situation that even has ajudge issuing a warning to cool it ... or else.

We're told Brad has been spending thebulk of his Summer in England -- where Angelina and the kids live -- so he can see his 6 children.

The judge inthe divorce case set out a schedule for Brad to visit with his children in London beginning in mid-June for 10 hours a day. The visitation increased last month to 4 consecutive days at a time.

Our sources say Brad and Angelina never interact with each other, and thehandoffs are always through nannies and assistants.  It's clear there have been issues over Brad interacting with the kids. The judge in the divorce case already issued an order saying Angelina tried torestrict Brad's accessthat the judge believed was "harmful" to the children.

via tmz.com

The judge even said Brad had a right to call and text the kids whenever he wanted, and Angelina could not monitor the contacts.TMZ broke the stories about Angelina claiming Brad has onlyprovided minimal child support, and Brad fired back in legal docs thathe's paid her$1.3 milin child supportsince theysplitnearly 2 years ago ... and he loaned her $8 million to buy a house.From what we're told, things are getting worse, not better, between the two.