Civil rights activist Jesse Jackson criticized Cleveland Cavaliers owner Dan Gilbert on Sunday for "arrogant" remarks about departing superstar LeBron James.

Jackson blasted Gilbert over comments calling James "cowardly," made after James announced he would leave Cleveland - where he has played all seven of his NBA seasons - for the Miami Heat.

"He speaks as an owner of LeBron and not the owner of the Cleveland Cavaliers," Jackson said a statement from his Chicago-based civil rights group, the Rainbow PUSH Coalition. "His feelings of betrayal personify a slave master mentality.

"He sees LeBron as a runaway slave," Jackson said. "This is an owner employee relationship - between business partners - and LeBron honored his contract."

Jackson said Gilbert's comments were an attack on all NBA players that should be challenged by the league and the players' union.

James, the biggest star in a star-studded 2010 crop of NBA free agents, announced on Thursday that he would leave Cleveland to play in Miami alongside Dwyane Wade - who opted to stay with the Heat - and Chris Bosh - formerly of Toronto.

His decision - breathlessly awaited by fans and several teams across the country - was a huge blow to long-suffering Cleveland sports fans. His decision to announce the move on a one-hour special on cable sports channel ESPN was criticized by some as egotistical.

Maybe so, but the Nielsen Company estimated that 9.95 million people watched the programme dubbed by ESPN "The Decision".

That made it the third-most watched programme on cable television in 2010, although the ratings paled in comparison to the 28 million people that Nielsen estimates watched game seven of the NBA finals, in which Kobe Bryant and the Los Angeles Lakers beat Boston for their second straight league title.

While Cleveland continued to lick its wounds - a huge downtown mural of James was being dismantled over the weekend - Miami continued to celebrate.

The NFL's Miami Dolphins took out a full-page ad in Sunday editions of three area newspapers thanking Wade for staying and welcoming James and Bosh to South Florida.

"Congratulations to the Miami Heat organization on a huge week," read the advertisement, underscoring the friendly relationship between the two teams.