Washington CNN  — 

It’s July 2019 in Washington, and President Donald Trump is again attacking Paul Ryan, a feud that might have died with the former House speaker’s retirement in January.

But the on-again, off-again duo is back in the spotlight thanks to new comments in a forthcoming book and Trump has found the time to punch back about Ryan’s assertions the President doesn’t understand government.

“American Carnage” by Politico’s Tim Alberta depicts a Republican Party that at first struggled with Trump’s rise during the campaign before gradually coming to terms with him as President, according to a report by The Washington Post, which obtained a copy of the book.

Alberta writes that Ryan left Congress in January because he couldn’t bear the thought of another two years with Trump and saw retirement as an “escape hatch.” In conversations with Alberta after retirement, Ryan, who had served nearly two decades in Congress, claimed Trump, a former real estate mogul, was ignorant about politics.

“I told myself I gotta have a relationship with this guy to help him get his mind right,” Ryan says in the book, the Post reported. “Because, I’m telling you, he didn’t know anything about government … I wanted to scold him all the time.”

“Those of us around him really helped to stop him from making bad decisions. All the time,” Ryan says. “We helped him make much better decisions, which were contrary to kind of what his knee-jerk reaction was. Now I think he’s making some of these knee-jerk reactions.”

In a series of late-night tweets Thursday, Trump blasted Ryan.

“Paul Ryan, the failed V.P. candidate & former Speaker of the House, whose record of achievement was atrocious (except during my first two years as President), ultimately became a long running lame duck failure, leaving his Party in the lurch both as a fundraiser & leader,” Trump wrote on Twitter.

“He had the Majority & blew it away with his poor leadership and bad timing. Never knew how to go after the Dems like they go after us. Couldn’t get him out of Congress fast enough!” Trump said in another tweet.

The pair have had an uneasy relationship since Trump became a candidate in 2015. Ryan wouldn’t immediately endorse Trump after it became clear he would become the party’s presidential nominee, citing his calls to deport millions of undocumented immigrants and proposed Muslim ban – though he would later support Trump’s travel ban that largely affected Muslim-majority countries – and he distanced himself from Trump after the infamous “Access Hollywood” tape surfaced.

After Trump’s election victory, he and Ryan worked together with some success to enact a Republican legislative agenda, most notably tax cuts, but the Republican-controlled Congress was unable to pass border wall funding, for which Trump blamed Ryan.

And although Ryan did his best to avoid answering questions when it came to Trump’s conduct as President, the Wisconsin Republican occasionally criticized Trump on issues like tariffs and his embrace of Russian President Vladimir Putin.

Ryan made no mention of an “escape hatch” when he announced his retirement last April, instead saying he wanted to spend more time with his family.

At the time, Trump wished him well.

“Speaker Paul Ryan is a truly good man, and while he will not be seeking re-election, he will leave a legacy of achievement that nobody can question. We are with you Paul!” Trump wrote.