"I have already discussed football with Bruce Arena and I know exactly what he wants from me," Keane added. "I am fit, fresh and ready to go. I've come here to score goals and help this team achieve their goals.
"This is a massive opportunity for me in my career. I aim to grab it with both hands and hopefully help give the Galaxy fans what they want."
DID YOU KNOW...
That Robbie Keane's combined transfer fees add up to £72.5m?
Keane made 254 appearances for Spurs during his first spell at the club between 2002 and 2008, scoring 107 goals.
He moved to Liverpool in July 2008 but spent only six months at Anfield before returning to White Hart Lane.
But he failed to hold down a regular first-team place, amid competition from Jermain Defoe, Roman Pavlyuchenko, Rafael van der Vaart and Peter Crouch.
Arena said: "Robbie Keane will be a great addition to our club.
"I have followed his career and have always respected his ability as a competitor and a goalscorer."
A statement on the
said: "The club can announce that it has reached agreement with Major League Soccer side LA Galaxy for the permanent transfer of Robbie Keane.
"We wish him all the best for the future."
The striker has scored 51 goals in 108 games for Ireland and 123 in 306 games in all competitions during his two spells at Spurs.
He started out at Wolverhampton Wanderers before joining Coventry City in 1999 for a then British record fee for a teenager.
Twelve goals in 34 games earned a move to Inter Milan where he spent 18 months before joining Leeds United.
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