Kevin Federline wants additional custody of the couple's sons

The troubled star and Kevin Federline, who divorced in July, are battling over custody of their two young sons.

People magazine and TV station KNBC will argue at a hearing in September that the papers should be made public.

But Mr Federline and Ms Spears will both fight the move. Mr Federline's lawyer said the papers included details that could put the boys in jeopardy.

When the pair's divorce was finalised in July, their lawyers won a conditional order to keep the records sealed.

Security information

On Tuesday, Los Angeles Superior Court Commissioner Scott Gordon delayed ruling on a request by their lawyers to make that order permanent.

After the hearing, Mr Federline's lawyer Mark Vincent Kaplan said the documents contained schedules and other details that could put the youngsters in danger.

"It would be best for the children that they not be exposed," he said. Ms Spears' lawyer Laura Wasser did not comment.

Lawyer Alonzo Wickers, who represents People and KNBC, said the former couple had been unable to prove that their concerns outweighed the public's right of access to court records.

Spears 'risks'

Celebrities "have to meet the same high burden" to justify the sealing of court records as other people, he said.

Ms Spears, 25, and Mr Federline, 29, have shared joint custody of their sons, 22-month-old Sean Preston and 10-month-old Jayden James, since February.

Mr Kaplan said Mr Federline was seeking additional custody because the two boys were "isolated from risks" when they were with him.