US President Donald Trump made his first public appearance on Saturday since returning to the White House after his hospitalisation for the coronavirus, welcoming hundreds of supporters to the South Lawn just weeks before the election. Mr Trump addressed the large crowd even as the White House refuses to declare that he is no longer contagious, against the guidance of public health officials. He told the crowd that he “was feeling great” and that a Covid-19 vaccine would be ready “very, very soon”. US science and medicine would "eradicate the China virus", Mr Trump added. Authorities stepped up security around the White House, where Mr Trump spoke. Police and the Secret Service closed surrounding streets to vehicles and shut down Lafayette Square, the park near the White House that has long been a gathering place for public protest. As questions remain about his health — and Democratic opponent Joe Biden steps up his own campaigning — Mr Trump also planned to leave the Washington area on Monday for the first time since he was hospitalised for a campaign rally in Sanford, Florida. He is also scheduled to hold campaign events in Iowa and Pennsylvania next week and is increasing his radio and TV appearances with conservative interviewers, hoping to make up for lost time with just over three weeks until Election Day and millions already voting. The president has not been seen in public — other than in White House-produced videos — since his return days ago from the military hospital where he received experimental treatments for the coronavirus. Most in the crowd that gathered for his speech on supporting law enforcement wore masks, but there was little social distancing. Saturday’s speech comes two weeks after his Rose Garden event that has been labeled a “superspreader” for the virus. More than two dozen people linked to the White House have contracted Covid-19 since the president’s September 26 event announcing Judge Amy Coney Barrett as his nominee to the Supreme Court. On Saturday, all attendees are required to bring masks or will be provided with them, and also will be given temperature checks and asked to fill out a brief questionnaire. Attendees will be strongly encouraged to follow CDC guidelines, which include mask-wearing and social distancing. Mr Trump’s Monday event in Sanford, Florida, was originally scheduled to be held on October 2, the day after he tested positive for the virus. Ahead of his Saturday event, Mr Trump used Twitter to share news articles about problems with mail-in ballots in New Jersey, Ohio and Texas. He has repeatedly made unsubstantiated claims that universal mail-in voting is beset by widespread fraud. Mr Trump’s return to public activity came as Dr Anthony Fauci, the government’s top infectious-disease expert, cautioned the White House again to avoid large-scale gatherings of people without masks. He said of the Barrett event in an interview with The Associated Press, “I was not surprised to see a superspreader event given the circumstances.” That means “crowded, congregate setting, not wearing masks. It is not surprising to see an outbreak,” he said. In a Friday night interview on Fox’s Tucker Carlson’s show, Mr Trump was asked if he has been retested for Covid-19. “I have been retested, and I haven’t even found out numbers or anything yet. But I’ve been retested, and I know I’m at either the bottom of the scale or free,” he said. White House officials, however, have declined to answer when Trump last tested negative for the virus or release detailed information about lung scans taken while Mr Trump was in hospital. Aides to the president insist that it is safe for Mr Trump to return to his regular activities, including campaigning. Centers for Disease Control and Prevention guidelines call for the infected to wait at least 10 days from the onset of symptoms, Fauci noted in the AP interview. That onset for Trump was October 1, according to his doctors. The president’s White House physician, Navy Cmdr. Sean Conley, added that Mr Trump was showing no evidence of his illness progressing or adverse reactions to the aggressive course of therapy he has received.