DENVER -- The controversy that erupted after a Mexican flag was shown hanging in one of the city's high schools has led officials to draft a policy protecting the display foreign flags in schools.

The guidelines, which are still being written, will allow flags of other countries to be temporarily displayed if they are related to what is being taught in the classroom, school superintendent Jerry Wartgow said Thursday.

The district got complaints from people upset by a photograph in the Rocky Mountain News showing a Mexican flag displayed in a social studies classroom at North High School on the first day of classes this week. Other people were upset that the American flag hanging beside it was hung improperly.

Wartgow said some callers didn't think there should ever be any non-U.S. flags in schools.

"It's a school for God's sake. That's where you study countries," he said.

By Friday afternoon, Wartgow issued guidelines that said non-U.S. flags will not be permitted in DPS schools.

"Only the United States or Colorado flags, or the flags of state subsidiaries, may be displayed permanently in schools," he siad in a news conference. "Temporary flag displays that are instructional or historic in nature or student work products used as part of a lesson are permitted."

North High School, where 83.6 percent of the students are Hispanic, received some threats over the flag flap, prompting Principal Darlene LeDoux to tell teacher Andrew Fox to remove the flag from his classroom. She also took down another Mexican flag which was displayed in the school's lobby along with a Statue of Liberty poster.

Fox, who was born in the United States and raised in Mexico, teaches English to Spanish-speaking students and said he hung the flag to make them feel more welcome.

Wartgow is planning on discussing his decision at a press conference Friday afternoon.