Updates share moves in second bullet point, adds companies' comments in sixth, seventh bullet points
** Shares in roll-on/roll-off (RoRo) shipping companies Wallenius Wilhelmsen WAWI.OL and Höegh Autoliners HAUTO.OL fall on Thursday, after the U.S. President unveiled a 25% tariff on all imported vehicles and foreign auto parts from April 2
** Wallenius Wilhelmsen is down about 9% in afternoon trade, while Höegh Autoliners shares slide 4.9%, narrowing earlier losses of 7%
** The tariffs could lead to a decrease in the volume of vehicles being shipped, as the cost for importing cars increases, DNB analysts say in a note
** SEB analysts view this as negative for the RoRo operators, potentially weakening the market balance and holding risk to the companies' contract backlogs
** In DNB's opinion Wallenius Wilhelmsen might be more sensitive to substantial sell-off, while Höegh Autoliners would be more affected by the higher spot exposure and secondary effects
** The two Norwegian car shipping companies told Reuters in their respective written statements that they were monitoring the situation
** "We have seen the news and will spend the next few days assessing what this will mean in collaboration with our customers," Höegh Autoliners CEO Andreas Enger added
** Wallenius is on track for its worst week in five years, if losses hold
** At 1535 GMT STOXX 600 autos & parts index .SXAP is down around 1% to its lowest in two months
(Reporting by Agnieszka Olenska, Marie Mannes)
((Agnieszka.Olenska@thomsonreuters.com;))