Editor's note: This story has been updated to reflect a spokeswoman for U.S. Sen Ted Cruz did not have a comment on Dan Patrick's interview. 

Speaking on The Laura Ingraham Show on Monday, Lt. Gov. Dan Patrick warned U.S. Sen. Ted Cruz will be left "in the rearview mirror of the Republican Party" if he doesn't endorse Donald Trump.

Cruz came under fire from Republicans earlier this year when he refused to endorse Trump during a primetime speech at the Republican convention in Cleveland. Patrick had been somewhat quiet about Cruz in the weeks following the convention, when speculation mounted that Cruz's refusal to endorse Trump would earn him a primary challenger in 2018. 

But when Ingraham asked about Cruz and other Republicans who won't support Trump on Monday, Patrick said he was "disappointed."

"You know, I stay loyal to my friends, and Ted’s a friend, but obviously I’m disappointed," Patrick said. "I’m hoping there’s still time for him to come forward or I think he and all the other people you named will be left in the rearview mirror of the Republican Party moving forward. So I’m hoping Ted comes forward. I’m visiting with him on that issue, of course.”

A spokeswoman for Ted Cruz declined to comment.

Patrick backed Cruz's own presidential efforts during the primaries. But after Cruz left the race, Patrick quickly became the most vocal advocate for Trump in Texas. Last week, Patrick was named Trump's Texas state chairman. He's also been a frequent attendee at Trump's rallies and fundraisers in Texas.

"My primary goal is to unite our party in Texas," Patrick said in a statement on Friday. "I want to ensure a solid Trump win and to remind Republican voters, and the new Trump voters who came out in the primary, to support the entire Republican ticket from the White House to the courthouse."

Read more about Donald Trump and Dan Patrick:

• Lt. Gov. Dan Patrick is taking an official role with the campaign of Republican presidential nominee Donald Trump, serving as his Texas state chairman.
• Republican presidential nominee Donald Trump made an unusual general election swing through Texas with a series of events — some public — planned across the reliably red state.  
• Republican presidential nominee Donald Trump used a Saturday trip to Houston to address families of victims of crimes committed by undocumented immigrants — and blast Democratic rival Hillary Clinton as unsympathetic to their concerns.

Patrick Svitek contributed to this report.