Andriy Yarmolenko has left Borussia Dortmund after one season to sign a four-year contract with West Ham United, the club announced on Wednesday.
Yarmolenko's arrival continues new manager Manuel Pellegrini's overhaul of the squad, with midfielder Jack Wilshere, goalkeeper Lukasz Fabianski and defenders Issa Diop and Ryan Fredericks joining the club this summer.
"We are very happy to welcome Andriy," West Ham director of football Mario Husillos said in a statement. "When we had the opportunity to sign him, we did not hesitate, because he really is the kind of player that we were looking for."
West Ham did not disclose the fee they paid Dortmund to acquire the 28-year-old, although reports said it was around £17.5 million.
Yarmolenko, whose 35 goals for Ukraine are second only to Andriy Shevchenko, scored 137 goals in all competitions in nine years at Dynamo Kiev.
He scored six goals in 26 appearances last season for Dortmund, who signed him in a €25m move last summer after losing Ousmane Dembele to Barcelona.