PORTLAND, Ore. -- U.S. soccer icon Landon Donovan will retire from the sport at the end of the current Major League Soccer season, he revealed on Thursday.

Donovan, 32, is the top goal scorer in MLS history as well as the top scorer in U.S. national team history. In a post on his official Facebook page, Donovan discussed his decision to step down:

"I don't write these words lightly and this day carries mixed emotions for me. I am sad to leave a profession that has brought me so much joy. However, after spending half my life as a professional soccer player, I also am excited to begin a new chapter and pursue other opportunities that will challenge me and allow me to grow as a person."

Speaking at a news conference later on Thursday, Donovan said the timing of his announcement was designed in part to give the Los Angeles Galaxy -- his club for the past decade -- time to reshape in his absence.

"I wanted the Galaxy to have the right amount of time to do what they want to do next," he said. "I also want to have some peace of mind going into the end of the season. I want to enjoy the last few months of my career."

The announcement comes one day after Donovan was named MVP of the MLS All-Star Game for scoring the winner against German powerhouse Bayern Munich -- which Donovan called "a perfect moment."

Donovan has four goals and seven assists in 17 games for the Galaxy this season as a midfielder and a forward, but said he felt relieved to step away.

"I made this decision a couple of weeks ago before the Seattle game [on July 28], and the way I've felt and played and enjoyed myself since then I think is reflective in a way of a weight off my shoulders. Now it's time to enjoy the rest of the season and there'd be no other way than to go out a champion, so that's my focus.

"My gut just told me it was right and that it was time. After a lot of conversations -- some pleasant, some not so pleasant -- with friends, family, people I respect and admire, I felt it was the right thing to do. It was important for me to do it."

Donovan said he will stay in the sport in some capacity, though he said coaching was not on his immediate agenda.

"We'll see, potentially," Donovan said on the prospect of coaching. "I absolutely want to work with kids. I spoke to [the Galaxy] extensively about working with the academy. That for me would be a good way for me to come full circle. I fully expect for that to happen at some point."

Donovan had agreed to a multiyear contract extension with the Galaxy just a year ago, pronouncing himself revitalized after an extended self-imposed sabbatical from the sport.

He took several months off after winning the Galaxy's second straight MLS Cup in December 2012 and spent some time in Cambodia.

Donovan will bring to a close an illustrious career which has seen him earn 156 caps for the United States, in which he scored 57 goals and had 58 assists -- both national team records.

He played in three World Cups (2002, 2006 and 2010), scoring five goals, including a dramatic group-winner against Algeria in 2010, but was omitted from Jurgen Klinsmann's squad for this year's tournament in Brazil. He has said he was surprised and disappointed by Klinsmann's decision, feeling he had done enough in training camp to warrant inclusion on his fourth team.

Asked on Thursday if his decision to retire was related to being left off the World Cup squad, Donovan said it was not, but let his feelings on the matter show clearly.

"I've always made decisions in my life for my happiness," Donovan said. "I certainly wasn't going to let one person's poor choice this summer affect a decision like this."

At the club level, Donovan is a five-time MLS Cup winner and was league MVP in 2009. He also holds league records for goals in the regular season (138) and playoffs (22) and won the Golden Boot in 2008.

The Southern California native began his professional career with Bayer Leverkusen in Germany before making his MLS debut in 2001 with San Jose, where he won championships in 2001 and 2003.

A return to Leverkusen followed, after which Donovan joined the LA Galaxy. He won his first MLS Cup with the Galaxy in 2005 but it would be six years before Donovan won his fourth, alongside fellow designated players David Beckham and Robbie Keane.

He also spent a brief, forgettable time on loan to Bayern Munich in 2009, but enjoyed more successful loans with Everton in the Premier League in 2010 and 2012.

Galaxy coach Bruce Arena, who also coached Donovan on the U.S. national team until 2006, called the midfielder a "first-class person."

"It's an unbelievable legacy," Arena said. "I have a hard time thinking that there's another American player that's accomplished as much as Landon has. A champion at the club level, a force on the national team, he's really been the focal point of our game for so many years. He's accomplished everything that an American player can accomplish at this point in time."

Asked about his legacy, Donovan said he hoped his time in the sport helped grow MLS and American soccer in general.

"I hope that my teammate will say I was a good teammate. I hope my coaches will say they enjoyed working with me and having me on their team. I hope the fans enjoyed watching and can see how much I gave over the last 16 years," Donovan said.

"That's really it, at the end of the day, the accolades -- the goals and assists -- don't mean a whole lot, but the relationships matter."

Information from The Associated Press was used in this report.