The House Coronavirus Pandemic Subcommittee on Wednesday demanded for the Centers for Disease Control and Prevention to hand over phone records of conversations between Director Rochelle Walensky and American Federation of Teachers President Randi Weingarten.

Committee Chairman Brad Wenstrup, an Ohio Republican, expressed his concerns about “potential political interference” in a letter to Walensky asking for the records after Weingarten told Congress she had the CDC head’s direct phone number.

Earlier this month, messages obtained through a Freedom of Information Act request from the Fairfax County Parents Association showed that Walensky had a friendly relationship with Weingarten and National Education Association President Becky Pringle. Weingarten’s and Pringle’s unions together have about 4.7 million members.