Nebraska's Republican governor has endorsed a primary challenger to sitting Congressman Jeff Fortenberry (R-Neb.), who is accused of making false statements to federal investigators probing his 2016 campaign contributions.

Gov. Pete Ricketts on Friday announced he is supporting state Sen. Mike Flood (R) in the Republican primary for Nebraska's 1st Congressional District.

“Mike will be able to focus his entire energy on representing the first district here in Nebraska and stopping this radical agenda coming out of D.C., and that's why I'm so proud to be able to endorse him in this primary to be the next congressman from the first congressional district," Ricketts said, according to KETV-TV.

Flood launched a primary challenge against Fortenberry last week, following the nine-term congressman's announcement that he would seek re-election again even though he was indicted by the Justice Department on multiple felony charges last fall. He faces three felony charges, including for lying to federal agents about the source of $30,000 in illegal campaign contributions.

Authorities claim that a group in California funneled money from Nigerian billionaire Gilbert Chagoury to Fortenberry's 2016 campaign. Fortenberry has plead not guilty to the charges.

Earlier this month, the congressman asked a federal judge to have the charges against him dismissed, but the judge denied his request.

Former Gov. Dave Heineman joined Ricketts in endorsing Flood over Fortenberry, writing in a letter that the allegations against Fortenberry are disqualifying.

"In modern political times in Nebraska, Jeff Fortenberry is the only Nebraska Congressman that has ever been indicted on felony criminal charges. His actions have resulted in a dilemma for Nebraska's first district voters," Heineman said. "We respect and appreciate his service, but we don't want to risk losing the seat to a Democrat. Therefore I'm supporting and endorsing Mike Flood for Congress."

In making the case for his candidacy, Flood has said the criminal allegations against Fortenberry will jeopardize Republican control of his congressional seat and hamper GOP efforts to retake the House majority in November.

"I've been talking to people in Fremont, Columbus, Norfork, Lincoln and all other communities. They're very apprehensive and concerned about this legal dilemma that he's in," Heineman told KETV.

"We're here today because of the situation Congressman Fortenberry is in because of his indictment,” Flood said last week when he announced his campaign.

In a statement Friday, Fortenberry responded to the endorsements for Flood.

“Today’s announcement is particularly disappointing because I have counted these people as friends and you hope you can rely on your friends to stand by you when you face adversity like a false and unjust accusation," Fortenberry said. "However, I’ve been very happy to receive endorsements for my re-election from business, community and political leaders across the First District. The voters will pass their own judgement on the character of the candidates in this race and I will spend this year talking with them about the accomplishments, leadership and conservative values that make me the best person to earn their vote and represent them in Congress.”