Barack Obama was livid when he found out that Donald Trump accused him of wiretapping Trump Tower.

The former president thought Trump’s claim questioned both the integrity of the office and himself, people familiar with him told the Wall Street Journal late Tuesday night.

Others told CNN that Obama was “irked, exasperated” and “in disbelief.” Another added that Trump’s predecessor “rolled his eyes” at the news.

Terrible! Just found out that Obama had my "wires tapped" in Trump Tower just before the victory. Nothing found. This is McCarthyism! — Donald J. Trump (@realDonaldTrump) March 4, 2017

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! — Donald J. Trump (@realDonaldTrump) March 4, 2017

As he prepared to leave office in January, Obama promised to speak out only if he thought “core values” were being violated. He has broken his silence twice now — once to praise protesters who were rallying against Trump’s immigration ban and once to respond to claims he wiretapped Trump.

“A cardinal rule of the Obama administration was that no White House official ever interfered with any independent investigation led by the Department of Justice,” Obama spokesman Kevin Lewis said in a statement Sunday.

“As part of that practice, neither President Obama nor any White House official ever ordered surveillance on any U.S. citizen. Any suggestion otherwise is simply false.” (RELATED: Obama Dropped This Statement In The Middle Of Sean Spicer’s Press Briefing Today)