(CNN) The Justice Department broke its days-long silence Friday on how it will comply with a federal judge's order requiring migrant children to be kept with their parents apprehended at the US border, but it also publicly called the court's attention to a glaring conflict with its sister court's order.

Friday's unsolicited filing from the Justice Department appears to be a strategic one to force the issue.

Last week, department lawyers sought to modify a decades-old settlement agreement in Flores v. Reno and subsequent court rulings that limit the detention of immigrant children to 20 days. Justice Department lawyers want US District Judge Dolly Gee in the Central District of California, who signed the operative decision in the case, to modify that rule to give the Trump administration greater flexibility in handling family units, because officials want to detain the parents not only until the end of any criminal proceedings but also through the end of any asylum proceedings, which could drag on for months.

Convincing Gee to make such a change to the agreement will be tough: The Obama administration tried it and failed.

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