Andersen, a non-executive director on Unilever's board since 2015, comes in alongside Scotsman Alan Jope who took over as CEO earlier this year. He replaces Marijn Dekkers, who is standing down after more than three years as chairman.

Jope wants to carve out more market share for Unilever's foods, but faces a challenge in low-growth categories like tea, bouillon, mayo and condiments. Unilever has changed internal leadership of foods twice in the last two years, but sales still remain muted in the business known for Hellmann's mayonnaise and Magnum ice-cream.

He also faces signs of a slowdown in India and China, two of the company's biggest markets. The Sino-U.S. trade war and sluggish domestic consumption are weighing on China's economy and irregular monsoons have curbed rural spending in India.

Andersen, 61, joined Unilever after heading shipping giant AP Moller Maersk A/S and brewer Carlsberg A/S.

At Maersk, where he served as CEO between 2007 and 2016, he was credited with bringing customer centricity and exceeding international growth targets, but the stock price fell a third during his tenure and the board decided to steer the old conglomerate in a new direction.

At Carlsberg, where he ran the company since 2001, the share price doubled in the two years before he moved to Maersk.

His predecessor at Unilever, Marijn Dekkers, who is founder and chairman of investment and advisory firm Novalis LifeSciences, will remain on the board as a non-executive director.

Dekkers became a target of investor ire last year for trying to consolidate the Lipton tea maker's dual headquarter structure in Rotterdam, dropping London.

The plan, devised with Unilever's former Dutch CEO Paul Polman, was scrapped after shareholders opposed the move on fears it could remove one of UK's best known companies from the benchmark FTSE 100 index.

Unilever's shares have risen 12% so far this year, outpacing the broader FTSE 100's 9% rise. The stock was up 0.6% at 4,622 pence in afternoon trading.

Andersen currently is part of Unilever's audit committee and serves as chairman of Dutch paint company Akzo Nobel NV and privately held Danish retailer Salling Group A/S. He is also a non-executive director at BP.

He intends to step down from his roles at BP and Salling Group A/S in March 2020, the company said on Wednesday.

(Reporting by Siddharth Cavale and Tanishaa Nadkar in Bengaluru and Stine Jacbosen in Copenhagen; Editing by Bernard Orr & Elaine Hardcastle)

By Siddharth Cavale