A New York prosecutor has announced he will convene a grand jury to probe the death last month of a 43-year-old black man placed in a chokehold by police.

Eric Garner, a father of six who was suspected of illegally selling cigarettes, was wrestled to the ground by several white police officers after resisting arrest in Staten Island on 17 July.

An amateur video showed police subduing him with a chokehold.

Mr Garner lost consciousness and was pronounced dead of a heart attack after being transferred to a hospital.

Classified as a homicide by the New York medical examiner's office, his death set off intense reactions and several protests in New York reminiscent of those in Ferguson, Missouri, over the August 9 police shooting of unarmed black teenager Michael Brown.

"Based upon the investigation that my office has conducted to date regarding the July 17, 2014, death of Eric Garner, and after a careful review of the recent findings of the Medical Examiner regarding the cause and manner of Mr Garner's death, I have determined that it is appropriate to present evidence regarding the circumstances of his death to a Richmond County Grand Jury," said Staten Island prosecutor Dan Donovan.

He said he expects the grand jury to be empaneled and begin hearing evidence sometime next month.

"I am committed to conducting a fair, thorough, and responsible investigation into Mr Garner's death," he said.

The amateur video showed Mr Garner, who was obese and asthmatic, pleading that he could not breathe as police held him to the ground.

The police officer who had Mr Garner in a chokehold has been identified as Daniel Pantaleo, who was suspended after the incident.

The grand jury, a civilian panel that hears testimony behind closed doors, is traditionally charged with deciding whether there is sufficient evidence to bring charges.

The prosecutor's announcement comes as civil rights activists including Al Sharpton have called a protest for Saturday on Staten Island, one of New York City's five boroughs, to demand justice for both Mr Garner and Mr Brown.