CMO Keith Weed, who oversees the marketing strategy of the world's second-biggest advertiser, announced his retirement on Thursday in a series of posts on Twitter.

"It's with a happy and heavy heart that I've decided to retire from Unilever in April," Weed said on Twitter. "It's been over a year in planning with exciting challenges to follow."

Choosing a successor will be a decision for the new chief executive, Alan Jope, who will take over at the start of 2019, a spokeswoman said.

(Reporting by Martinne Geller; editing by David Evans)