“The dimensions of this are huge," Sen. John McCain said. | AP Photo McCain on Trump's wiretap claim: 'I haven't seen anything like this'

Sen. John McCain on Monday demanded the release of any evidence backing up President Donald Trump's claim that President Barack Obama wiretapped Trump Tower in the run-up to the presidential election, blasting the White House’s refusal to answer additional questions about the matter.

McCain said the American people “have a right to know on what basis the president of the United States said that his predecessor had broken the law by wiretapping Trump Tower.”


“I haven't seen anything like this,” the Arizona Republican told reporters, explaining that the Trump administration “should answer questions.”

“The American people should demand it,” McCain continued. “The dimensions of this are huge.”

He said his first reaction upon reading Trump’s tweet on Saturday morning was “intense curiosity.”

“This is unprecedented,” he added. “I have never heard of a president of the United States accusing his predecessor or any other president of the United States of violating the law.”

Trump on Saturday tweeted: “Terrible! Just found out that Obama had my ‘wires tapped’ in Trump Tower just before the victory. Nothing found. This is McCarthyism!”

Former Director of National Intelligence James Clapper later cast doubt on the allegation, saying on NBC's "Meet the Press," "I can deny" the existence of a court order allowing the FBI to wiretap Trump Tower.