WASHINGTON — President Donald Trump will deliver a primetime address this week that he says will include a focus on elections, suggesting he could revisit long-debunked conspiracy theories about his 2020 defeat to Democrat Joe Biden. The speech comes as he’s escalated calls for Republicans to pass tighter federal voting rules for November’s midterm elections.

The Republican president has been guarded about what he plans to say in the 9 p.m. Thursday speech, scheduled as he confronts a collapsing deal to end the war with Iran. He also faces numerous domestic issues, including recent deadly shootings by Immigration and Customs Enforcement officers. Asked for a preview of the speech on Tuesday, Trump offered scant detail but said he has “really big news.”

“It doesn’t get bigger, because without free and fair elections, you don’t have a country,” Trump said in the Oval Office. He refused to go further, saying he wanted to “save it” for the moment, though he also hinted he would be talking about a hodgepodge of issues.

“We’ll be discussing other things, too,” Trump said, without elaborating. “It’s going to be a very big announcement.”

Trump has used the power of the primetime presidential address — typically reserved for milestones — to deliver politically charged speeches before, including one in December when he sought to blame the challenging economic climate on Democrats. But Thursday’s address seems poised to go even further, using the moment to amplify election lies before an audience of millions in an effort to boost Republican prospects before midterms that threaten to hobble Trump for the remainder of his term.

On Monday, when asked about the speech, Trump repeated baseless claims of voter fraud in the Los Angeles primary race for mayor. During the interview with conservative outlet Newsmax, Trump said Republican Spencer Pratt lost his primary bid because of fraud, citing in part California’s slow vote count.

Federal prosecutors said they were opening fraud investigations in the state last month after Trump drew attention to the claim.

The president’s preoccupation with voting fraud and election security dates back at least to 2016, when he refused to say whether he would accept defeat to Democrat Hillary Clinton. After he won, he convened a voting integrity commission to support his claims that widespread voter fraud cost him the popular vote, though the commission disbanded without uncovering any such evidence.