Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

Charleston, South Carolina — A pro-Ted Cruz super PAC launched a robocall on Thursday night to Republicans across South Carolina, attacking Donald Trump’s support for the removal of the Confederate battle flag from the state’s Capitol grounds last summer.

The 60-second robocall plays audio of Trump saying, "Let it go. Put it in a museum." Trump’s voice continues, "Respect whatever it is that you have to respect because it was a point in time."

"That’s Donald Trump supporting Nikki Haley removing the battle flag from the Confederate memorial in Columbia," the ad’s narrator says.

Courageous Conservatives, the pro-Cruz super PAC who paid for the calls, intends to send out two new robocalls on Friday night as well — just hours before the polls open for the state's GOP primary.

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Rick Shaftan, the head of the group, told NBC News the robocall about Trump’s opposition to the flag went out to 180,000 homes of Republicans who have voted in past primaries in South Carolina.

Haley, the governor of South Carolina, endorsed Cruz’s other main rival, Marco Rubio, on Wednesday.

Haley called for removing the battle flag from the Capitol grounds and the state legislature voted to bring it down after a white gunman fatally shot nine people at a historic black church in Charleston in a racially-motivated attack.

“A lot of people are very upset with Nikki Haley for that decision,” Shaftan said. "People feel very strongly about that. It’s not the right thing to do, especially among conservative Republicans.”

In the ad, the narrator says, "Donald Trump talks about our flag like it’s a social disease.”

A new poll released by left-leaning Public Policy Polling released this week suggests 70 percent of Trump's supporters think the Confederate battle flag should fly on the state Capitol grounds.

Shaftan, who lives in North Carolina, said he "couldn’t believe" Trump took the position to remove the flag, contrasting it with Cruz who said at the time that the decision should be left up to those in the state.

“People feel very strongly about it here, especially Trump supporters," Shaftan said. “That’s what surprised me — to see people who support the flag also supporting Trump. We’re trying to reach those folks who are having second doubts [about Trump].”

Shaftan said the ad could be used in other states as well, He dismissed any notion that ad could be interpreted as a "dirty trick" because the ad's content is now public.

In the last two weeks, several of the Republican candidates have traded barbs over the use of robocalls in the South Carolina race.

He said the super PAC spent $25,000 in radio and robocall advertising in South Carolina this last week. It just bought $10,000 worth of radio air time in Nevada as well through Tuesday.