West Ham have eased their striking problems with the signing of Livorno forward Alessandro Diamanti.

The 26-year-old, who joins the Upton Park club for an undisclosed fee, has signed a five-year contract with the Hammers.

He told his new club's official website, www.whufc.co.uk: "I am very happy to be at West Ham United and to get the chance to play for Gianfranco Zola."

Hammers boss Zola, who needed to strengthen his forward line, had been tracking Diamanti for several months.

The only senior frontline striker currently fit at Upton Park is Carlton Cole, with Dean Ashton a notable absence through injury.

He continued on the Hammers' website: "I chose West Ham because the club have the tradition of playing great football. Also, because the West Ham fans are really passionate and that is the way I am."

The club's chief executive Scott Duxbury said: "I am delighted we have been able to secure this transfer at last as we feel that Alessandro will be a perfect complement to our existing attacking options.

"It has been a case of working around the clock to ensure we landed another of our key targets and the three of us are grateful for the supporters' understanding of what we are trying to achieve with our exciting squad."

The Hammers had been strongly linked with a move for Diamanti after failing to land Bordeaux's Marouane Chamakh. Lazio's Goran Pandev had been another player the Barclays Premier League club had reportedly showed an interest in.