Donald Trump’s campaign manager said Thursday that there’s a “conflict” within the campaign regarding endorsements of primary candidates, following controversy over Trump’s hesitation to endorse a couple high-profile Republicans.

“There’s a conflict within the Trump campaign, and we’ve sort of had a rule of not getting involved in primaries because it’s usually not a good situation for the presidential candidate,” Paul Manafort said Wednesday morning on Good Morning America.

Trump hasn’t yet endorsed Republican House Speaker Paul Ryan, saying “I’m just not quite there yet”—a phrase that echoed Ryan’s initial hesitation to endorse Trump as the presidential nominee. But Indiana Gov. Mike Pence, Trump’s running mate, offered his endorsement of Ryan on Wednesday. “I strongly support Paul Ryan, strongly endorse his reelection,” he said.

Ryan eventually endorsed Trump in June, but has since repeatedly voiced disagreement with some of Trump’s policies and public comments. Meanwhile, Trump tweeted at Ryan’s primary opponent, Paul Nehlen, this week.

“Of course he’s going to work with Paul Ryan, of course he’s tried to bridge the party together with Paul Ryan, but Ryan is also running against somebody who’s not going to win but nonetheless is a strong supporter of Mr. Trump’s,” Manafort said on Wednesday, about Trump. And he said Trump’s hesitation to get involved will apply to other primary races.

“It’s not just in Paul Ryan’s district,” Manafort said. “That gets all the notoriety because he’s the Speaker.”

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Write to Katie Reilly at Katie.Reilly@time.com.