Russell Crowe says his ex-wife felt ''uncomfortable'' wearing the jewellery he's selling off in a divorce auction.

The Academy Award-winning actor separated from Australian singer Danielle Spencer in 2012, and is now planning to sell off some of her eye-catching jewellery, which he says the blonde beauty hardly ever wore because it made her feel awkward around her friends.

One of the items up for auction is an 18-carat white gold diamond ring, which he says cost him ''$160,000 or something at the time''.

Appearing on The Kyle and Jackie O Show, Russell explained: ''She's worn it a couple of times and that's the thing with Dani, she's a very humble person.

''I'd given her diamond rings, and necklaces and bracelets ... she felt that she was putting her friends in an uncomfortable position.

''So she put stuff away - she put the comfort of her friendships and stuff before her own enjoyment.''

Russell has sons Charles, 14, and Tennyson, 11, with Danielle, after they started dating in 1989, having co-starred in the Australian movie 'The Crossing'.

And the 53-year-old actor has admitted Danielle thought he was joking when he first mentioned the idea of staging a divorce auction.

He shared: ''I told her what I was doing and she thought it was really funny but I think for a period of time she thought it was a concept I'd come up with purely for amusement.''

Meanwhile, Russell previously claimed that the auction was designed to help him put their marriage - which was officially ended in 2017 - behind him.

He said: ''Divorce has its way of making you really examine the things that are essential in life - and the things that are not.

''Through the process I had a look around and realised I had a lot of stuff. Career stuff, stuff I've collected, and stuff in general. Boxes and boxes of stuff ... so in the spirit of moving forward into fresh air, here's a portion of that collection of stuff.''