** Shares in Vallourec VLLP.PA fall 8%, among top losers on the STOXX 600 .STOXX, after ArcelorMittal MT.LU sold a 10% stake in the French steel tubes maker at a discount for $667 million
** ArcelorMittal sold 23.9 million shares via an accelerated bookbuild at 24 euros each, a nearly 8% discount to Monday's close of 26 euros
** ArcelorMittal retains 17.3% stake in Vallourec following deal
** "Stake sale in VK may come a surprise to some investors," says Jefferies
** "However, this was prior to the YTD rally in VK shares. From MT (ArcelorMittal) perspective, the return of investment has been attractive," it adds
** Vallourec has gained 75% since ArcelorMittal built its stake in 2024 for $995 million, and is up 66.2% YTD
(Reporting by Gianluca Lo Nostro)
((gianluca.lonostro@thomsonreuters.com;))