Richard Riordan on Wednesday resigned his post as Gov. Arnold Schwarzenegger’s Secretary for Education, effective June 30, and said he will return to Los Angeles.

Riordan, the former Los Angeles mayor who was one of the first cabinet officials tapped by Schwarzenegger after the Oct. 2003 recall election, said in a statement that he had actually submitted his resignation in March, but agreed to Schwarzenegger’s request to serve until a replacement is found.

Riordan and Schwarzenegger had been friends long before Schwarzenegger named him to the education post. They worked together on a successful statewide ballot measure for after school programs. However that friendship was tested when Schwarzenegger announced he was running for governor in the recall election. Until that announcement, Riordan had been regarded as the Republican frontrunner.

Riordan’s departure from the education post had long been the subject of speculation. Critics said that he had accomplished little and seemed out of place in Sacramento. The criticism escalated last year after he insulted a child at a reading promotion event in Santa Barbara, calling her a “stupid dirty girl.” Riordan later apologized, but not before his gaffe made nationwide headlines.

In recent weeks as Schwarzenegger’s proposed education reforms encountered resistance from teachers’ unions, rumors were circulating that Riordan might be leaving.

Riordan is still of counsel to his downtown L.A. law firm, formerly called Riordan & McKinzie LLP, which is now part of Bingham McCutchen LLP. He could not be reached to discuss his future plans. In his resignation announcement he said, “I will continue working to improve not only education, but the quality of life for all Californians. I am hard-wired to get things accomplished and have done so in both the public and private sectors.”