WASHINGTON — (CNN) The Republican National Committee has a message for candidates like Donald Trump: No more name-calling.

That’s what the party’s chief strategist and communications director Sean Spicer said on CNN’s “Reliable Sources” on Sunday.

“I understand it’s going to be the nature of any primary for folks to discuss the differences between themselves on policy issues, and I think that’s fine,” Spicer said. “The name calling, however, needs to stop.”

Spicer added: “We have got to remember what Ronald Reagan taught us, his 11th commandment, ‘Thou shall not speak ill of another Republican.'”

Spicer didn’t point his comments directly at Trump or any other candidate, but it’s Trump who has been receiving the most attention for insulting his rivals in recent weeks.

Trump has called Lindsey Graham an “idiot,” labeled Jeb Bush an “unhappy person” who is “out of touch,” and has mocked Rick Perry’s glasses. On Saturday, after a fundraiser for Scott Walker criticized Trump, Trump called the event “very dumb” and “not smart.”

Other candidates have been critical of Trump, as well. Sunday on CNN’s “State of the Union,” Perry said of Trump, “What he is saying and what he is doing is not necessarily moving the cause of conservatism forward.”

The RNC has been treading lightly when it comes to Trump, the party’s unexpected frontrunner in the 2016 presidential campaign.

Spicer’s overarching message on Sunday was that “we have to keep our eye on the prize,” winning back the White House.

In calling for no more name-calling, Spicer was echoing RNC chairman Reince Priebus. In a Friday night appearance on Fox News, Priebus also invoked the “Reagan’s 11th commandment” and said he was tired of the in-fighting between candidates.

“I think it needs to stop from whatever source, from every place,” Priebus told Fox’s Greta Van Susteren.

Spicer said the party organization has been in “constant interaction with all the campaigns,” including Trump’s, and “that will continue.”

“We’re not here to play traffic cop,” he said. “But I think we can remind people about what it’s going to take to win. Our number one goal is to win the White House back… We have to remember that calling each other names is not exactly helpful in the long term.”

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