The committee said it plans to schedule the hearing for after Memorial Day.
Senate Democrats pounced after a report that President Trump asked FBI Director Comey to halt his probe of Mike Flynn, NBC News reports.
Democrats also renewed their call for a special prosecutor in the investigations into Russia's meddling in the 2016 election.
The Senate Select Committee on Intelligence has issued a subpoena for former national security advisor Michael Flynn.
The Senate Democratic leader said that such an appointment would be necessary for restoring American people's confidence in the case.
First Read is a morning briefing from Meet the Press and the NBC Political Unit on the day's most important political stories and why they matter.
The mothers of Trayvon Martin and Eric Garner, whose deaths sparked protests about racial profiling, are among the speakers at the Democratic convention.