Breaching the usual standards for courtesy in the Senate, Ted Cruz one of the Republican presidential hopefuls said the leader of his party had violated his trust over a federal bank.

In an attack that stunned many, Cruz on Friday accused Mitch McConnell the majority leader in the Senate of lying and saying he was not to be trusted.

The Texas senator, who ranks quite low in the early polls regarding the race for the White House in 2016, delivered the speech Friday on the floor of the Senate.

Cruz claimed that McConnell had given him assurances that there had not been any deals made on allowing a vote for the renewal of the Export-Import Bank, which is a a federal agency that is little known. Cruz delivered his remarks just moments after majority leader arranged a vote for the agency for an upcoming session.

Cruz said it saddened him to have to say it, but he had earlier told his staff that the Senate majority leader had looked him in the eye along with 54 Republicans and he could not believe he told a lie. Cruz said he voted based on the assurances that McConnell had made to all the Republicans.

At the time of Cruz’s speech, McConnell was not present on the floor of the Senate and would not respond to reporters who asked him about the incident in the hallways of the Capitol.

Cruz and McConnell have not had a good relationship from the start. The majority leader’s allies had earlier in the year derided the Senate record of Cruz complaining he often spoke out then would skip important sessions.

After making a complaint about the nomination by President Obama of Loretta Lynch to be the attorney general, Cruz skipped her final confirmation vote.

Some people near to McConnell called Cruz Mr. One Percent, which refers to the amount of support amongst the crowded GOP field vying for the party’s presidential nomination.

Cruz of late has grown more and more outspoken over his contempt of both McConnell as well as other members of the Republican Party.