Rep. Adam Schiff, D-Calif., wants the House Intelligence Committee's investigation into Russian interference in the 2016 election to look at whether President Trump obstructed justice.

"I think it needs to be part of the investigation," Schiff, who is ranking member on the intelligence panel, told Politico on Thursday. "Congress has to get to the bottom of whether anybody is interfering or obstructing any investigation in any way."

Schiff said he's spoken to Rep. Mike Conaway, R-Texas, who is leading their committee's probe, about looking into obstruction of justice.

Schiff's comments come one day after the Washington Post reported that the special counsel, Robert Mueller, is expanding to include whether Trump committed obstruction of justice in order to hinder the Russia investigation.

Trump tweeted early Thursday that the obstruction of justice probe is based on a "phony" collusion story.

Another committee running its own investigation into Russian meddling, the Senate Intelligence Committee, will not look into possible obstruction of justice. "The criminal piece of the investigation will be handled by the special counsel, but if we find facts, we can turn this over to the special counsel," said Sen. Mark Warner, D-Va., vice chairman of that committee, told CNN.