Jury selection was delayed on Monday in the high-profile trial of the white police officer accused of killing George Floyd, a Black man whose death was captured on video and sparked mass protests against racial injustice in the United States and around the world.

As hundreds of protesters gathered near a heavily guarded Minneapolis courthouse, Hennepin County Judge Peter Cahill ordered jury selection put off until at least Tuesday.

Prosecutors had asked for it to be paused until an appeals court can rule on whether the judge should reinstate a third-degree murder charge against former Minneapolis police officer Derek Chauvin.

"The court will be seating jurors for a trial about which we don't know what the exact charges are going to be yet," said Matthew Frank, the lead prosecutor.

Chauvin, 44, is currently facing charges of second-degree murder and manslaughter in connection with Floyd's May 25, 2020 death.

Second-degree murder carries a maximum sentence of 40 years in prison while the lesser charge of third-degree murder carries 25 years.

The visibly impatient judge said he believed selection of the 12 jurors and four alternates should go ahead but he agreed to hold off while the appeal is pending.

He later said jury selection would begin at 9:00 am Central Time (1500 GMT) on Tuesday.

"Unless the court of appeals tells me otherwise we're going to keep moving," the judge said.

While jury selection has not formally begun, prosecutors and Chauvin's defense attorney did mutually agree on Monday to dismiss 16 members of the initial pool of 50 jurors.

Both sides also agreed to submit a list of witnesses to the court by March 22 and prosecutors agreed to winnow down their current list of 362 potential witnesses. 

Chauvin, who has been free on bail, appeared in court wearing a dark blue suit and a face mask at a desk surrounded by plexiglass as a Covid-19 precaution.

He occasionally jotted down notes on a yellow legal pad. 

 - Racial wounds -
Chauvin was dismissed from the police force after he was captured on video by a bystander with his knee on the neck of a pleading, gasping Floyd for nearly nine minutes.

Floyd's death laid bare racial wounds in the United States and sparked months of sometimes violent protests against racism and police brutality, both in the US and abroad.

Lawyers for both sides face the difficult task of finding jurors who have not already made up their minds about the widely publicized case.

Jury selection is expected to take up to three weeks, with arguments slated to begin on March 29.

Three other police officers involved in Floyd's arrest -- Alexander Kueng, Thomas Lane and Tou Thao -- face lesser charges and will be tried separately.

All four officers were fired by the Minneapolis Police Department.

Floyd's arrest was prompted by accusations that he had tried to pass a counterfeit $20 bill in a nearby store.

Among the protesters gathered in Minneapolis on Monday was Marcus Smith, who stood on a sidewalk using a karaoke machine to address a crowd carrying "Black Lives Matter" posters and pictures of Floyd.

"There's a problem in America," Smith told AFP. "The problem is the system we're fighting. Cops get acquitted in a racist system."

Nadi McDill, a young black woman, said she supported delaying the trial because filing the third-degree murder charge against Chauvin may increase the chances of conviction.

It's important, McDill said, "not to have all the eggs in the same basket."

 - 'Exactly as he was trained to do' -

Chauvin's case is being watched as a potential marker of change in a country that recently elected its first Black vice president but has seen police officers historically escape punishment for abusive acts.

It will feature gripping testimony, as foreshadowed Sunday by Benjamin Crump, a prominent civil rights attorney representing the family of the 46-year-old Floyd.

"You look at the video, and you hear him say 28 times, 'I can't breathe,'" Crump told ABC's "This Week." 

Amid the Covid-19 pandemic, social distancing rules mean seating will be limited at the trial, with the Floyd and Chauvin families given only one seat a day. 

Despite intense global interest, only two reporters will be allowed in. The trial is being livestreamed.

Lawyers for Chauvin, a 19-year veteran of the force, have argued that he was following police procedure and claimed Floyd died of an overdose of the drug fentanyl. 

"Mr. Chauvin acted according to MPD policy, his training and within his duties," according to his lawyer, Eric Nelson. "He did exactly as he was trained to do."

An autopsy did find traces of fentanyl in Floyd's system but said the cause of death was "neck compression."

A verdict is not expected until late April.