Members of the panel, which held what was expected to be its final hearing before the midterm elections Thursday, had previously said that they were still considering seeking an interview with Trump or former Vice President Mike Pence. Sources familiar with the committee's plans told NBC News of the subpoena earlier Thursday.
The panel's chair, Rep. Bennie Thompson, D-Miss., said the panel had an "obligation" to hear from Trump.
"This is a question about accountability to the American people. He must be accountable. He is required to answer for his actions," Thompson said, acknowledging the move as a "serious and extraordinary action."