Rep. Jim Sensenbrenner has become the butt of blogosphere jokes after reportedly making an unflattering remark about first lady Michelle Obama's derriere. 

Sensenbrenner, who is not exactly svelte himself and could never rock a sleeveless like the first lady does, apparently went there while talking to someone over the phone at Reagan National Airport outside Washington, D.C. The blog FishbowlDC first reported that he was overhead recalling a conversation he had a few weeks ago at a church auction. 

According to the account, Sensenbrenner, R-Wis., said he told a woman who was praising Obama -- who has pushed her "Let's Move!" campaign and others to improve childhood eating habits -- that she should follow her own advice. 

"She lectures us on eating right while she has a large posterior herself," Sensenbrenner reportedly was overheard saying. 

Sensenbrenner, who does not deny making the comments, plans to call the first lady's office to apologize, according to an aide. 

"Mr. Sensenbrenner was referring to the first lady's healthy food initiative. He doesn't think the government should be telling Americans what to eat. While he may not agree with all of her initiatives, he plans to contact the First Lady's office to apologize for his comments," spokeswoman Amanda Infield said. 

Infield told FoxNews.com that call will likely happen Thursday.