He will be eligible to make his first-team debut once the Secondary MLS Transfer Window opens on June 15.

David Beckham is due to move to the Galaxy from Real Madrid at the end of the current Spanish season.

The 34-year-old former Liverpool and Everton player joins on a free transfer after he was released by Middlesbrough last week. The confirmation rules out any rumoured move of Xavier coming to the A-League. The defender has been linked to Adelaide United in recent weeks.

Galaxy president and general manager Alexi Lalas told the club's official website: "Abel brings immense experience and a wonderful personality to our team.

"He's a great defender and we're excited that he's coming to LA."

Xavier had a turbulent spell at the Riverside after moving on transfer deadline day in August 2005.

In October that year he was banned from playing football for 12 months after failing a drugs test.

He rejoined Middlesbrough in November 2006 after serving the ban and made 20 appearances in 2006-07 before manager Gareth Southgate decided Xavier was surplus to requirements.

Xavier said: "I'd like to thank Alexi Lalas, Frank Yallop and MLS for this opportunity.

"Soccer is my life and I'm excited to continue my career in LA. Soccer in the United States continues to grow and I'm proud to be a part of it.

"I'm coming to win. With the great team and wonderful fans at the LA Galaxy everything is possible. I bring heart, hunger, desire and passion. This is me today, tomorrow, and always."

Head coach Frank Yallop added: "This is a terrific signing for us and he will bring so much experience, leadership and ability to the team.

"People of his quality are not often available for us to sign, so we are really happy that he is going to join us."

The Mozambique-born player has 20 caps for Portugal, scoring twice.