(AP) -- Ohio State says football coach Jim Tressel has resigned as the NCAA investigates the Buckeyes for possible rules violations.

The university announced the resignation Monday. Tressel says in a statement that he met with university officials and agreed that it is in Ohio State's best interest that he resign.

The school says Luke Fickell, an assistant head coach under Tressel, will serve as interim head coach for the 2011-2012 season.

University President E. Gordon Gee says the university's "public purposes" and "tradition of excellence" are guiding its actions.

The text of Jim Tressel's resignation letter tendered on Monday to Ohio State athletic director Gene Smith:

Dear Gene:

After meeting with university officials, we agreed that it is in the best interest of Ohio State that I resign as head football coach.

The recent situation has been a distraction for our great university and I make this decision for the greater good of our school.

The appreciation that (wife) Ellen and I have for the Buckeye Nation is immeasurable.

We have been blessed to work with the finest group of young men in America and we love them dearly.

In addition, we cannot thank you enough. ... the high school coaches we have worked with over these many years.

We know that God has a plan for us and we will be fine. We will be Buckeyes forever.

Jim Tressel

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