The first-ever Birkin bag designed by French luxury brand Hermes for celebrity Jane Birkin sold for 8.58 million euros (US$10 million) at a Sotheby's auction in Paris on Thursday, smashing previous price records for a handbag.

The modern design classic, owned by a Paris-based handbag collector, sparked a telephone bidding war up to seven million euros, with the final sale price set at 8.58 million with commission and fees, the Sotheby's website showed.

"After weeks of anticipation, the bidding opened at 1 million euros - prompting a gasp from the room," Sotheby's said in a statement.

The final buyer, who eclipsed eight other rivals, was a "private collector from Japan", the auction house added, without giving further details.

The previous record price for a handbag at auction was set by a diamond-encrusted crocodile skin Hermes Kelly 28, which fetched US$513,000 in 2021 at Christie's in Hong Kong.

Sotheby's had advised that the Birkin prototype was expected to beat that level during its sale.

But the staggering price tag for a well-worn item is in keeping with the fashion world's recent flashy aesthetics.

After years of so-called "quiet luxury" dominating catwalks, designers have embraced more ostentatious looks in recent seasons that have been dubbed "boom boom" by some trend forecasters.

Modern-day Birkin bags are offered by Hermes to loyal clients, with prices starting at around US$10,000. (AFP)