FRANKFURT - Kuwait's sovereign wealth fund, Mercedes-Benz's third-largest shareholder, is planning to reduce its stake in the German luxury carmaker via the sale of 20 million shares, according to bookrunners.

At price guidance of 69.27 euros apiece, this could rake in 1.385 billion euros ($1.5 billion) for the Kuwait Investment Authority (KIA), which would reduce its stake to less than 5% from 6.84% now.

"The KIA is committed to continuing the successful partnership with Mercedes-Benz and will remain a key shareholder," Mercedes-Benz said in e-mailed comments.

Frankfurt-listed shares of Mercedes-Benz were 2.3% lower following the news.

($1 = 0.9225 euros)

(Reporting by Christoph Steitz Editing by Mark Potter)