In a strikingly fierce speech on the Senate floor, Sen. Ted Cruz (R-TX) repeatedly accused Senate Majority Leader Mitch McConnell of lying about a deal to vote on reauthorizing the Export-Import Bank.
"Whether we are Democrats or Republicans, these 100 senators have to be able to trust that when a senator says something, he or she will do it even if we disagree on substance, that we don't lie to each other," said Cruz, who is seeking the Republican nomination for president.
While political discourse on Capitol Hill is often harsh, Cruz's accusation on the Senate floor that the leader of his own party knowingly lied is highly unusual.
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Cruz attacked McConnell moments after the Kentucky Republican lined up a vote for Sunday to reauthorize the bank after its expiration last month. Cruz claims McConnell told him three times no deal had been cut to reauthorize the bank in order to get votes for a trade package that moved through the Senate earlier this year.
"Like St. Peter, he repeated it three times," Cruz said on the floor, recounting his conversation when McConnell told him there was no deal.
The Texas senator accused McConnell of using the same tactics as Democratic predecessor Harry Reid, and he suggested that McConnell deceived not only him but the rest of the party and the press.
"What we just saw today was an absolute demonstration that not only what he told every Republican senator but what he told the press over and over and over again was a simple lie," Cruz said.
He continued: "This institution should not operate at the beckon call of lobbyists in Washington. This institution, the majority and minority leader arm in arm, again, should not team up against the American taxpayers."
McConnell's office had no comment in response to the speech.
This article first appeared on NBCNews.com.