The daughter of a US woman whose body was found stuffed inside a suitcase at an Indonesian resort island has changed her plea to guilty in Chicago federal court on charges that she helped kill her mother during a Bali holiday nine years ago.

Heather Mack, 27, was convicted in Indonesia in 2015 of being an accessory to Sheila von Wiese-Mack’s murder with her then-boyfriend in a bid to gain access to a $US1.5 million ($A2.2 million) trust fund.

Mack, then 18 and pregnant, covered her mother’s mouth in a hotel room while Tommy Schaefer bludgeoned Wiese-Mack with a fruit bowl, prosecutors say.

Mack stood before US District Judge Matthew Kennelly in orange jail garb and orange slippers as he asked her questions before she was set to enter a plea.

She spoke confidently and calmly as the judge asked her if she was giving up her rights to remain silent at the motion hearing.

“Yes, your honour,” she responded from a podium.

After the judge explained the charge against her, Mack pleaded guilty to one count of conspiracy to kill a US citizen.

The change-of-plea hearing is the latest chapter in a story that garnered international attention in part because of photographs of the suitcase, which seemed too small to hold an adult woman’s body.

Mack’s Chicago trial on conspiracy to commit murder in another country and obstruction of justice had been set for August 1.

The judge set a December 18 sentencing date for Mack.

Her plea deal calls for a sentence of no more than 28 years.
Mack, who lived with her mother in suburban Chicago’s Oak Park, served seven years of her 10-year Indonesian sentence.

She was then deported in 2021 and US agents arrested her immediately after she landed at Chicago’s O’Hare International Airport.

Schaefer was convicted of murder and remains in Indonesia, where he is serving an 18-year sentence.

He is charged in the same US indictment.

Before Mack’s conviction in Indonesia, she gave birth to her and Schaefer’s daughter.

Her then-six-year-old daughter was with her when Mack was arrested at the Chicago airport.

The girl was later placed with a relative after a custody fight.

In successfully arguing against bond for Mack, prosecutors said she and Schaefer had planned the killing for months.

They also said they had video evidence that showed both Mack and Schaefer trying to get the suitcase with Wiese-Mack’s body inside it into an Indonesian taxicab.

Some relatives of Wiese-Mack had complained that the Indonesian sentence was far too lenient.

In filings, prosecutors said the US charges do not violate constitutional prohibitions against prosecuting someone twice for the same acts, including because the US charges allege conspiracy and other acts not included in the Indonesian case.

— AAP