Top members of the House Intelligence Committee said Wednesday they have seen no evidence to support President Donald Trump‘s claim that Trump Tower was wiretapped ahead of the 2016 election.

“We don’t have any evidence. … I don’t think there was an actual tap of Trump Tower,” the chairman, Republican Rep. Devin Nunes of California, told reporters.

Ranking member Rep. Adam Schiff, D-Calif., also said he had not seen information to support that accusation against former President Barack Obama, which Trump made without citing evidence. Schiff said lawmakers will ask FBI Director James Comey about the issue during a public hearing Monday on the investigation into Russian influence on the U.S. election.

Nunes and Schiff initially gave the Justice Department a Monday deadline to turn over any evidence backing the allegation, but it has asked for more time. Schiff said lawmakers still want the Justice Department to respond to their letter asking for information.

The White House previously asked Congress to add Trump’s wiretapping claims to its ongoing probes into the extent of Russian influence on the 2016 U.S. election. The American intelligence community concluded that Moscow meddled, first aiming to harm then-candidate Hillary Clinton and then developing a preference for Trump.

The White House said earlier this week that the evidence would vindicate Trump for his claim made in a tweet earlier this month, though it has so far not provided any. Press secretary Sean Spicer appeared to say that Trump’s “wiretapping” accusation could have meant broader surveillance activities that are not limited to a physical wiretap at Trump Tower.

Separately on Wednesday, Attorney General Jeff Sessions told reporters he did not give Trump a reason to believe he was wiretapped. Sessions said he could not comment further because he recused himself from investigations related to the Trump campaign, following revelations that he met twice with Russia’s ambassador to the U.S. while serving as a senator and Trump campaign advisor.

Nunes said Wednesday that Trump’s wiretapping claim, if taken literally, is wrong. But he added that he still wants to figure out if other surveillance took place, saying he wants more information on intercepted communications related to people associated with the Trump campaign, including ousted National Security Advisor Michael Flynn.

Some lawmakers have raised concerns about the contacts between people associated with the Trump campaign and Russia, but Trump has called any suggestion of ties a politically charged witch hunt.

Nunes said National Security Agency Director Michael Rogers also will attend Monday’s hearing.