President Donald Trump will use a primetime address on Thursday to make the case for new election integrity measures, an issue central to his political movement since he alleged the 2020 White House contest was stolen by Democrats and former President Joe Biden.

Trump offered few details about his surprise address to the nation slated for Thursday at 9 p.m., but he told reporters in the Oval Office this week that the announcement would concern elections and would be “really, really big news.”