Arena revealed the news, which is expected to be officially announced later on Wednesday, in an interview with the LA Times.
“Steven Gerrard arrives in July and by then we will certainly have a plan available,” Arena told the newspaper.
“He’s a player of quality. I’m not concerned about how he’s going to fit in with our team.
“We have a club now with a proven history of success. All those things go hand in hand in making LA Galaxy a very attractive team for players such as Steven Gerrard.”
Galaxy president Chris Klein described the former England midfielder as “the perfect fit” for Galaxy who have won the Major League Soccer title in three of the last four years.
Klein said: “We just started thinking in the universe of players that are out there, we want to make a decision on what signifies a Galaxy-designated player.
“When we look at that, Steven Gerrard is the perfect fit with what he brings to us on the field and the character that he has off it.”
In announcing his decision to leave Liverpool,??Gerrard stressed he could not play for another European club??if there was a chance they would come up against his boyhood side, and he believes Galaxy is the ideal destination.
“I think it’s a match made in heaven really,” Gerrard told the newspaper.??”One of the reasons I chose LA Galaxy was because of the success they’ve had??recently.
“I want to finish my career very strong. I want to add some medals and??trophies to my collection.”