PARIS/LONDON (Reuters) - L'Oreal is to acquire British skincare brand Medik8, its owner, Britain-based private equity firm Inflexion, said on Monday, boosting the French cosmetics giant's offering in the fast-growing dermatological skincare market.

The size of the deal was not disclosed. Medik8 focuses on vitamin A-based anti-ageing creams and serums.

"The partnership with L'Oreal will allow Medik8 to deepen its presence in existing markets and expand globally. As part of the transaction, Inflexion will retain a minority shareholding in Medik8," the private equity firm said in a statement.

L'Oreal's dermatological beauty division, which includes major brands like CeraVe, La Roche-Posay, and SkinCeuticals, has been its fastest growing in recent years, reaching revenues of 7 billion euros ($7.99 billion) last year, after growing almost 10% on the year before.

The business, which also has the highest profit margin among its four divisions, has boomed on growing consumer interest in science-backed products, though growth has slowed recently due to rising competition.

L'Oreal executives said this year they were pursuing acquisitions and looking to revive flagging growth. The company acquired Korean skincare brand, Dr.G, in December and also bought a minority stake in Oman-based perfume house Amourage last year.

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