The Galaxy have failed to win any of their last seven games and it is proving to be another turbulent season for the California club and their star man, England captain David Beckham.

However, Gullit cited "personal reasons" in his decision to quit.

"Both parties have agreed on mutually-agreeable terms to part company," said Tim Leiweke, president of the AEG Group that owns the Galaxy.

"It is an amicable arrangement and we appreciate and respect the issues that Ruud has highlighted with the club and are very grateful for all the hard work he has contributed while with the organisation. Hopefully, he has laid the foundations for future success for the Los Angeles Galaxy."

While Gullit left of his own accord, the club chose to dismiss Lalas rather than wait for his contract to expire at the end of the season.

"With Ruud moving on, we believe that this is the right time to make more sweeping changes throughout the organisation," said Leiweke.

"Our commitment continues to be focused on not only winning the MLS Cup this and every season but to build a club capable of competing at the international level.

"This decision is the right one for the organisation, the right one for the players and the right one for our fans. We thank Alexi for the tremendous hard work and dedication he brought to his job each and every day."

The moves come as the Galaxy's poor run of form has dropped them out of the play-off spots in the Western Conference.

With 23 points from 19 games, they are only one point above city rivals Chivas USA - who they face on Thursday night - and, as things stand, would miss out on a post-season berth.

That does not match the expectations of a team that, with Beckham now fully fit, was supposed to challenge for the MLS Cup title this season.

Gullit took over as Galaxy coach during the close season following the departure of Frank Yallop to the San Jose Earthquakes.

The former Holland international brought with him lofty credentials as the former Newcastle and Feyenoord coach, but failed to turn around the fortunes of the Galaxy, and is thought to have been left frustrated by the limitations imposed by MLS regulations, most notably the salary cap.

In a statement, the 45-year-old also cited the difficulties of relocating his family to California.

"In truth, it has proved a lot more difficult than I anticipated for my family to settle in the area and the club has been very supportive and understanding of my decision," he said.

"I would like to thank the players and the fans for their fantastic support and I wish the LA Galaxy much success in the future. I would now like to spend some time with my family before considering any other position in football."

Gullit is to be replaced by former Galaxy star and assistant coach Cobi Jones on an interim basis.

Lalas was the man who appointed Gullit and oversaw the club's policy of pursuing high-profile names, signing Beckham, to play alongside Carlos Ruiz and Landon Donovan.

The policy has proved controversial in a league with a tight salary cap, as it leaves a very limited budget to spend on the remainder of the squad.

Lalas joined the Galaxy's front office from New York in 2006 after playing for the Galaxy from 2001 to 2003.

In his absence, the GM's duties will be carried out by Galaxy director of soccer Paul Bravo and assistant general manager Tom Payne.