West Ham have completed the signing of Arsenal midfielder Freddie Ljungberg for a fee that could rise to £3m.
Ljungberg says West Ham's ambition helped him decided to join
The Sweden international joined the Gunners in a £3m deal from Halmstads in 1998 and scored 72 goals in 325 games.
Arsenal boss Arsene Wenger wanted Ljungberg to stay but the 30-year-old said: "It was the right time to go.
"It was a difficult decision but when Thierry Henry left it felt like the end. I am coming here to build a great team and I am looking forward to it."
Ljungberg, who was Arsenal's longest serving player, struggled with injury last season and played just 26 games.
His former team-mate Henry left to join Barcelona in June and Ljungberg revealed his growing frustration at the Emirates Stadium.
It feels like a big challenge and I am really happy with it
Freddie Ljungberg on joining West Ham
"Two years ago when I signed my last contract we talked a lot about the future and about bringing great players to the club," Ljungberg explained.
"Despite building the new stadium we wanted to stay top in England and do well in Europe. For me that didn't really happen."
And the Sweden captain says he is relishing beginning the new season at Upton Park.
"When I spoke to Arsene Wenger, he wanted me to stay," Ljungberg added.
"But, at the same time, I feel it had to be something very, very special for me to leave.
"For me it is about why I wanted to join West Ham, not why I wanted to leave Arsenal.
"The reason I wanted to join is because of West Ham chairman Eggert Magnusson.
"He wants to take West Ham to the top of the country. He is willing to go on the market and buy great players and mix them with youth players from the academy.
"I am really happy to be here and he wants me to help take this club forward. It feels like a big challenge and I am really happy with it."
West Ham manager Alan Curbishley feels he was able to sign Ljungberg because of the other players who have arrived at the club this summer.
He follows Julien Faubert, Scott Parker, Craig Bellamy and Richard Wright into Upton Park.
"We spoke to Freddie over the last week and we tried to sell him the club and what we are about," Curbishley said.
"He has seen other players come in and push us forward."
"Freddie brings Champions League experience, being captain of Sweden and that he is versatile but the biggest thing is that there is a hunger there."