Washington - US President Donald Trump promised to cure cancer and eradicate Aids if re-elected at a huge rally to announce his campaign for a second term.
Trump also vowed to help put an astronaut on Mars as he addressed a 20 000-strong crowd in Orlando, Florida. Mr Trump, 73, told cheering supporters: "I promise you I will never ever let you down."
He vowed: "We will push onward with new medical frontiers. We will come up with the cures to...many, many diseases, including cancer.
"We will eradicate Aids in America once and for all. We will lay the foundation for landing American astronauts on the surface of Mars."
Former Democrat vice-president Joe Biden, 76, is front-runner to take on Mr Trump in the 2020 election.