Superior Court Commissioner Reva Goetz extended Jamie Spears' control until July 31, said court spokesman Alan Parachini. Parachini wasn't immediately able to provide more information on Wednesday.

James Spears was named co-conservator of the pop star's estate after she was hospitalised twice in January. His temporary authority to handle her affairs was to expire March 10.

In the year leading up to the hospitalisations, Spears had been caught on camera by paparazzi engaging in increasingly bizarre behaviour. She shaved her head, beat a vehicle with an umbrella, wore skirts sans underwear and left her car on a busy thoroughfare after getting a flat tire.

The strange outbursts and hospitalisations contributed to the 26-year-old losing custody of her young sons, Jayden James, 1, and Sean Preston, 2. Ex-husband Kevin Federline continues to have full custody.

Spears was allowed brief visits with the boys beginning in late February after not seeing them for nearly two months. That happened after Spears and Federline "agreed to a modification of the court's order" that had stripped Spears of her visitation rights, according to Federline attorney Mark Vincent Kaplan.

Spears' parents came to Los Angeles around the time of her second hospitalisation. They pushed to restore visitation rights with the boys.