The Grizzlies have given Lionel Hollins permission to speak to other teams after initial talks between Memphis and the coach stalled over what one source described as "major philosophical differences."

Hollins' contract with the Grizzlies expires at the end of the month. Both he and the team have said they hoped he would return to build on the most successful season in franchise history. But initial conversations on a new contract haven't been productive, leading the Grizzlies to give him permission to speak with other teams on Sunday.

The Brooklyn Nets and Los Angeles Clippers each have interest in Hollins, but no team has formally requested permission to speak to Hollins yet, a source familiar with the situation said Sunday.

Hollins told ESPN last month that Grizzlies management came to him during the first round of the playoffs to assure him that the franchise wanted to bring him back.

"The only conversations we've had is they said they wanted me back," Hollins told ESPN during the second round of the playoffs. "After we lost the first two games to the Clippers, we had a friendly conversation about the series and how they just wanted me personally to know that regardless of what's being said out there, this is how they felt. That was great."

Grizzlies point guard Mike Conley expressed a similar sentiment in an interview with ESPN last month.

"I know that he's fought for me in every situation that he's had to. I can't even put enough words in the sentences to say how much it means to me," Conley said. "Now I'm trying to go to bat for him, try and keep him here."

ESPN.com's Marc Stein reported in early April that Grizzlies management wants to retain Hollins, even after the coach's initially angry reaction to the late-January trade of Rudy Gay to Toronto. Yet it remains to be seen how much Memphis is willing to spend to keep him.

Doubts about Hollins' willingness to work for new Grizzlies owner Robert Pera and CEO Jason Levien have likewise been in circulation since the coach's multiple critiques of the Gay deal in its immediate aftermath. Sources told ESPN.com that Hollins' relationship with star forward Zach Randolph has been strained at times throughout the season as well.

Stein reported last month that assistant coach Dave Joerger would receive strong consideration to take over if Hollins departs.

Information from ESPN.com's Marc Stein was used in this report.