NORTH Melbourne caretaker Brett Ratten has urged Alastair Clarkson to take as much time as he needs to get his mental and physical health in order before returning to the club.

Clarkson will remain on leave despite the independent investigation into historical allegations of racism at Hawthorn ending.

It found former Hawks coach Clarkson, Chris Fagan and Jason Burt, who have strenuously denied all allegations, had not breached the League's rules.

Clarkson stepped away from his Kangaroos role last month as he dealt with the fallout from the racism saga.

Ratten will lead North Melbourne in Sunday's clash with Essendon – his third game in charge – and is unsure how long he will remain at the helm.

"I haven't spoken to Al, so we'll just let it take its course," Ratten told reporters on Thursday.

"We just need Al to look after himself and make sure he's in a good spot.

"When he's ready to come back, he'll come back and take over the reins.

"But you'd rather him take a little bit more time to get himself right instead of rushing back, so I think that's what he's doing.

"I'm not sure if it's one more week for me or eight more – I've got no idea."

Former St Kilda and Carlton coach Ratten, who was an assistant to Clarkson at Hawthorn during the premiership hat-trick, initially joined North Melbourne as a part-time mentor for the young midfield brigade.

The 51-year-old said the uncertainty around his role as caretaker coach is "not really" a challenge for him personally.

"When you come in and see players doing extras and all that, it's quite easy," Ratten said.

"They're doing the work so from a club point of view you can just see the players trying to improve, and that makes any coach's life easy.

"We've got really good assistant coaches doing a great job too ... so we've got really good people around to help us out."

North Melbourne (2-9) has lost nine consecutive matches ahead of taking on eighth-placed Essendon (6-5).