US President Joe Biden said Wednesday that Donald Trump had clearly backed an insurrection after Colorado's top court blocked the Republican from seeking a second term over the 2021 Capitol assault. "I'll let the court make that decision. But he certainly supported an insurrection. No question about it, none, zero," Biden told reporters after arriving in Milwaukee, Wisconsin aboard Air Force One. "It's self-evident. You saw it all," added the 81-year-old Democrat, who is likely to face Trump in a close-fought 2024 presidential election in a rematch of their 2020 battle.