David Frost, the controversial agent of imprisoned former NHL hockey player Mike Danton, has resigned as a player agent.

The NHL Players' Association announced Frost's resignation in a brief statement on Tuesday.

Frost's client list has been small, with Danton, a former St. Louis Blues centre, and Sheldon Keefe, a former Tampa Bay Lightning forward, being the most notable.

David Frost, longtime mentor and agent to imprisoned NHLer Mike Danton, resigned as an NHL player agent on Tuesday.

"There was really no need to stay on with the PA," Frost told cable sports network TSN. "Nobody pressured me out, believe me. If somebody tried to do that, I would have just stayed around out of spite."

Frost's name has been in the headlines over the past two years for his relationship with Danton, who was sentenced to 7½ years in a U.S. prison in November of 2004 for plotting to have Frost killed.

Frost has denied he was the intended target of the murder-for-hire plot.

Frost was back in the spotlight last week after the airing of "Rogue Agent," a documentary by CBC's the fifth estate.

The piece, hosted by Bob McKeown, follows the intertwining story of Frost and Danton from when the latter was an aspiring 10-year-old player named Mike Jefferson, to the present.

It also featured previously unheard jailhouse conversations that recorded Frost advising Danton to deny Frost was the target of the hit and to blame his emotional problems on his parents.

A day after the documentary aired last week, Danton's father, Steve Jefferson, was arrested and charged with criminal harassment after allegedly placing 22 phone calls over three days to Frost.

Jefferson has been ordered to appear in court on Jan. 10.

The NHL Players' Association recently launched an investigation into Frost's certification. As of Tuesday, Frost's name was taken off the list of certified player agents.