Sasse said if there was a legal authorization for a phone tap, then Trump should disclose that application. | Getty Sen. Sasse says Trump must elaborate on Obama tapping claims

President Donald Trump owes the public a further explanation of his allegation that former President Barack Obama tapped Trump's phones, said GOP Sen. Ben Sasse on Saturday afternoon.

The Nebraska Republican, who opposed both Trump and Hillary Clinton in the president campaign, called the current political atmosphere a "civilization-warping crisis of public trust" after Trump said Obama ordered Trump's phone lines tapped before the election and Obama's spokesman denied it on Saturday. Sasse said if there were taps, it would have been either with a FISA court authorization or without — but either way Trump needed to publicly explain his tweeted allegations.


"The president today made some very serious allegations, and the informed citizens that a republic requires deserve more information," Sasse said. "If without [an authorization], the President should explain what sort of wiretap it was and how he knows this. It is possible that he was illegally tapped."

But Sasse said if there was a legal authorization for a phone tap, then Trump should disclose that application.

"If it was with a legal FISA court order, then an application for surveillance exists that the court found credible. The president should ask that this full application regarding surveillance of foreign operatives or operations be made available, ideally to the full public, and at a bare minimum to the U.S. Senate," Sasse said.

Sasse is one of the first GOP senators to weigh in on Trump's series of Saturday tweets that compared Obama to former President Richard Nixon and former Sen. Joseph McCarthy, and called Obama "sick" for allegedly tapping his phone. Sen. Lindsey Graham (R-S.C.) said at a town hall that if Trump's allegation is true, it is the biggest scandal since Nixon's Watergate.

"Is it legal for a sitting President to be ‘wire tapping’ a race for president prior to an election? Turned down by court earlier. A NEW LOW!” Trump tweeted on Saturday morning. “I'd bet a good lawyer could make a great case out of the fact that President Obama was tapping my phones in October, just prior to Election!”

Obama's spokesman said that "neither President Obama nor any White House official ever ordered surveillance on any U.S. citizen."