West Ham have completed the club-record signing of Sebastien Haller from Eintracht Frankfurt for a reported fee of £45million.
The Premier League side agreed a deal on Tuesday with Frankfurt, who granted Haller permission to travel to London for a medical.
The 25-year-old has now signed a five-year deal with the Hammers, with the option of a further 12 months.
The striker becomes the most expensive signing in the club's history, eclipsing the reported £36m paid to Lazio for Felipe Anderson last year.
"I feel really great," Haller told West Ham's website. "I think it's a really good opportunity for me to be here.
"It means a lot [to be the record signing]. It proves that the club [has] really wanted me for a long time. I felt this desire to sign me and I'm really happy to sign, also. It is an ambitious club, a nice club, a nice city and nice fans too."
Haller scored 20 goals in all competitions in 2018-19, including five in Eintracht's run to the semi-finals of the Europa League.
He will be tasked with spearheading the West Ham attacking following Marko Arnautovic's move to Chinese Super League side Shanghai SIPG.
Manuel Pellegrini's side had been tipped to sign Maxi Gomez before turning their attentions to Haller after the Celta Vigo forward moved to Valencia.
"I will always give 100 per cent and respect the club," Haller added.
"I think this is a normal thing and that I can guarantee. I know it's a big transfer and there is a lot of expectation around me, and I just want to make people proud of this transfer and I will give everything I have."