Who to believe?
"Based on the information available to us, we see no indications that Trump Tower was the subject of surveillance by any element of the United States government either before or after Election Day 2016," Republican Chairman Richard Burr and Senator Mark Warner, the committee's Democratic vice chairman, said in a statement.
The top Republican in Congress, House of Representatives Speaker Paul Ryan, on Thursday added his voice to those saying there was no sign of a wiretap.
But White House spokesman Sean Spicer forcefully defended Trump's assertion during a briefing, citing media reports that have discussed intelligence collection on possible contacts between Trump associates and Russia in the campaign.
"There is no question that there were surveillance techniques used throughout this," Spicer said.