Florida lawyer John Rex Powell allegedly travelled to Queensland, France and San Francisco to sexually assault a young Australian boy.

A Florida lawyer accused of being a key member of a global pedophile network that used a young Australian boy as its centrepiece has indicated he will agree to a plea deal with prosecutors.

If John Rex Powell, 41, does plead guilty in an Indiana court it will be the latest conviction in the US for an investigation that began in New Zealand in 2011 and involved law enforcement agencies across the world, including the Queensland Police Service’s Taskforce Argos.

Last month, in Indianapolis Australian pedophile Peter Truong, 36, from Cairns, was sentenced to 30 years’ jail and in June, in the same court, his long-time American partner, Mark Newton, 42, was jailed for 40 years.

Truong and Newton bought the boy as a newborn for $US8000 ($A9020) from his mother in Russia and then passed him around for videotaped sex with pedophiles, including Powell, prosecutors allege.

Powell is also accused of sexually abusing an American boy.

His arrest shocked Florida’s legal fraternity.

He was scheduled to stand trial in Indianapolis on Monday, but his lawyers have asked the judge to push the trial back as he he may enter a plea.

“The parties have been engaged in lengthy debriefing sessions with the anticipation of reaching a plea agreement,” Powell’s lawyer, Kathleen Sweeney, told the judge.

Powell went by the screen name “thebeav” and travelled to the Cairns home where Truong, Newton and the boy lived, prosecutors said.

Powell allegedly had sex with the boy, then aged five or six, during the stay, as well as during a trip to France.

Video evidence obtained by authorities allegedly showed Truong, Newton, Powell, the boy and another man, Jason Bettuo, 36, visiting San Francisco Zoo and later Powell assaulting the boy on a hotel bed alongside the child’s stuffed toys.

Bettuo has been sentenced to 25 years’ jail.

The investigation began in 2011 when New Zealand and German authorities, working independently, uncovered evidence Truong and Newton “had travelled the world and provided access to their six-year-old son” for “the purpose of sexual gratification of adult males, and for the production of videos and images depicting sexual gratification”.