Britney Spears lawyer has branded the singer's father a 'reported alcoholic and gambling addict' and criticised his financial knowledge in new court documents.

Mathew Rosengart has his back at Jamie Spears after he objected to the attorney's request to replace him as the 39-year-old pop star's conservator with certified public accountant John Zabel, insisting the man was "unqualified" to take on the responsibility.

According to the court papers, which obtained by a media outlet, Mathew argued John is a "highly esteemed, nationally recognized, award-winning CPA with an impeccable record of serving in positions of trust."

He noted the accountant's accolades are “in stark contrast to Mr. Spears, a reported alcoholic and gambling addict, with zero financial background or experience in financial matters, who previously filed for bankruptcy and has a domestic violence restraining order currently in effect against him.”

The latter refers to an order forbidding Jamie from being around Britney's sons, 16-year-old Sean Preston and 15-year-old Jayden, following a "physical altercation" in September 2019.

Britney's attorney argued that appointing the accountant would 'also be supported by Ms Spears’ business management and forensic accounting teams.'

Jamie Spears had earlier filed a court document warning John would have to “hit the ground running” if he takes the job and insisted he lacked the experience and wisdom to manage the 'Gimme More' hitmaker's estimated $60 million fortune.