WASHINGTON, Feb 3 (Reuters) - U.S. President Donald Trump signed an executive order on Monday ordering the creation of a sovereign wealth fund within the next year, saying it could potentially buy the short video app TikTok. Trump offered little in the way of detail and it was unclear how such a wealth fund would work. Typically such funds rely on a country's budget surplus to make investments, but the U.S. operates at a deficit. Its creation also would likely require approval from Congress.