Designer Vaccarello to replace Slimane at YSL

French luxury group Kering is expected to announce as soon as Monday that Belgian designer Anthony Vaccarello will be the new creative director of fashion brand Yves Saint Laurent, a source told Reuters on Friday.

Vaccarello will replace Hedi Slimane, whose departure was announced earlier by Kering. The company declined to comment on the succession.

"It has been signed. It should be announced on Monday," the source with first hand of the matter told Reuters, on condition of anonymity.

Vaccarello, who specializes in designing the "little black dress" and is a fan of asymmetric designs, has been rumored as a potential replacement for Slimane as he will be able to provide more of the same rock chic designs that have proved so popular for the Yves Saint Laurent brand.

The source added that before Vaccarello accepted the job he agreed to stop developing his own brand and to focus solely on Yves Saint Laurent (YSL).

When Slimane arrived in 2012, he stamped his identity on Yves Saint Laurent and turned it into a grunge label that found favor among wealthy fashion-conscious buyers and became Kering's fastest growing brand.

Known for controlling everything from advertising campaigns that he shot himself to the content, look and feel of the brand's website, Slimane had renamed the label Saint Laurent, but Kering referred to the brand as Yves Saint Laurent in its statement on Friday.

Slimane helped more than double YSL's sales to 974 million euros ($1.1 billion), making it one of only a few fashion brands to have achieved revenue of around $1 billion, along with Qatari-controlled Valentino.

Analysts estimate YSL will contribute around 12 percent of Kering's operating profit growth over the next three years.

Citi analysts said YSL's strong sales growth "was partly driven by the favorable halo effect from a star designer like Hedi Slimane", as well as a successful transition into leather goods. They also noted its operating margin had reached a record 20 percent in the second half of 2015.

"We expect Kering management to have a credible contingency plan and be in a position to announce his successor soon," the Citi analysts said.

YSL sits alongside sister brand Gucci, which generates more than half of the group's operating profit. Kering also owns Balenciaga, Stella McCartney and Alexander McQueen, and controls sports brand Puma.

Slimane's departure comes as Christian Dior is still looking for a replacement after the unexpected departure of Raf Simons last autumn. Lanvin, meanwhile, has just appointed Bouchra Jarrar to replace Alber Elbaz, who left abruptly in October.