House Speaker Paul D. Ryan repeated Thursday that his endorsement of Republican presidential nominee Donald Trump was “not a blank check” and delivered a sharp critique of Trump’s flailing campaign two days after Trump declined to endorse Ryan for reelection to his Wisconsin congressional seat.

“He’s had a pretty strange run since the convention,” Ryan said on WTAQ radio in Green Bay. “You would think that we want to be focusing on Hillary Clinton, on all of her deficiencies. She is such a weak candidate that one would think that we would be on offense against Hillary Clinton, and it is distressing that that’s not what we’re talking about these days.”

Ryan’s comments came in his first live interview in more than a week, and they followed a near-constant string of Trump controversies, including his attacks on the parents of Capt. Humayun Khan, a Muslim American Army officer who was killed in Iraq War combat in 2004.

The Post’s Philip Rucker explains how unusual it is that Donald Trump is withholding his endorsements of Paul Ryan and John McCain in their primary races. (Bastien Inzaurralde/The Washington Post)

Ryan repeated some of his previous comments on Trump, telling host Jerry Bader that he was not inclined as a leader of the Republican Party to question the choice of the voters who made Trump the GOP nominee. “We are a grass-roots party; we aren’t a superdelegate party,” he said. “We are a party where the grass-roots Republican primary voter selects our nominee. And that’s as it should be…. And I think there’s something to be said about respecting those voters.”

“He won the delegates,” Ryan added. “He won the thing fair and square.”

But he made clear that he is deeply uncomfortable with Trump’s performance since becoming the nominee. He said Trump’s comments on the Khan family “were beyond the pale.”

“You don’t do that to Gold Star families,” he said. “If anyone has earned the right to say whatever they want, it is Gold Star families.”

Bader pressed Ryan on whether a moment would ever come where he would abandon Trump. Ryan repeated a line he has given previously — “none of these things are ever blank checks” — while acknowledging that he would remain behind Trump even after the Khan controversy while continuing to speak out against his various controversial utterances.

“I don’t like doing this; I don’t want to do this,” Ryan said. “But I will do this because I feel I have to in order to defend Republicans and our principles so that people don’t make the mistake of thinking we think like that.”

In a separate interview later in the day on Wisconsin Public Radio, Ryan was confronted with criticism he has received from fellow conservatives — including a Wall Street Journal column that argued Ryan was “doing his personal reputation and his party’s fortunes no favors with these evasions.”

Ryan called those critics “friends” but said they are situated differently: “They’re not the speaker of the House,” he said. “They’re not the highest elected Republican official representing Congress and the party. And I feel I need to respect our rules. The delegates voted for him. It’s a democratic system.”

He also emphasized the presidential power to nominate Supreme Court justices and referred to a “binary choice” between Clinton and Trump: “I know Hillary Clinton will put a bad judge from my perspective on the Supreme Court. I believe that Donald Trump won’t.”

Trump, meanwhile, has shown less adherence to the standard rules of party loyalty. On Tuesday, he told The Washington Post that he would not endorse Ryan in his primary fight against Paul Nehlen, a pro-Trump businessman who has slammed Ryan for his past support of trade deals and immigration reform. Then on Wednesday, Trump’s running mate, Indiana Gov. Mike Pence, broke with Trump and gave Ryan an unalloyed endorsement.

Speaking to ABC’s “Good Morning America” on Thursday, Trump campaign manager Paul Manafort said “there’s a conflict within the Trump campaign” about the Ryan primary.

“Of course, he’s going to work with Paul Ryan,” Manafort said. “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, he’s a strong supporter of Mr. Trump’s.”

At a rally later in the day, Trump called Ryan “a good guy” and suggested that he had assented to Pence’s endorsement, but he did not explicitly endorse Ryan himself.

Speaking on WTAQ, Ryan on Thursday dismissed Nehlen’s campaign as “desperate” and “powered by these scam PACs and with a lot of out-of-state people.”

“I don’t think Wisconsinites take kindly to this,” he said. “I feel very good where I am. The people here in Wisconsin know me and know me well.”

What Donald Trump is doing on the campaign trail

MANCHESTER, NH - NOVEMBER 7: Republican presidential candidate Donald Trump speaks during a campaign event at SNHU Arena in Manchester, NH on Monday November 07, 2016. (Jabin Botsford/The Washington Post)