A California doctor accused of giving Friends star Matthew Perry access to ketamine in the weeks before the actor's overdose death has agreed to plead guilty, according to federal prosecutors.

Dr Salvador Plasencia will plead guilty to four counts of distributing ketamine, federal prosecutors said in a statement on Monday.

The plea carries a maximum sentence of 40 years in prison, and the doctor is expected to make his plea in the coming weeks.

Perry – best known for playing Chandler Bing on Friends – was found dead in his hot tub in Los Angeles in October 2023.

He was 54, and although he'd been open about struggles with depression and addiction, fans around the world were shocked by his death.

According to text messages shared with prosecutors from Dr Mark Chavez - a doctor who already pleaded guilty in the case - Dr Plasencia called Perry a "moron" and wondered how much he'd be willing to pay for the drugs.

According to documents filed for the plea agreement, Dr Plasencia injected Perry with ketamine at his home and in the parking lot of the Long Beach Aquarium.

Dr Plasencia taught Perry's assistant, who is also a defendant, how to administer the drug and would sell extra vials for them to keep at home, according to the plea deal.

The doctor is one of five people charged with what prosecutors allege was an underground network of dealers and medical professionals who supplied Perry with ketamine. The actor was taking legal, prescribed amounts of the drug to treat his depression, but wanted more than what was prescribed.

In total, the plea agreement says, between 30 September 2023 and 12 October 2023, Dr Plasencia sold twenty 5ml (100mg/ml) vials of ketamine, less than a full package of ketamine lozenges, and syringes to Perry and his assistant.

Dr Plasencia's lawyers could not be immediately reached for comment.