She called them "four beautiful and very different countries" when talking about the details at a meeting on the sidelines of the UN General Assembly.

Mrs Trump said the trip will be organised with the US government's international aid agency and would be part of her Be Best campaign, which aims to improve child welfare, especially when it comes to online behaviour and addiction to opioids.

"Each of us hails from a country with its own unique challenges, but I know in my heart we are united by our commitment to raising the next generation to be happy, healthy and morally responsible adults," AP news agency quotes her as saying.