That was how much Obama sold them over 8 years but those deals are pretty much done. Trump has at most $4 billion in arms sales at risk.
Trump is a moron for making these statements, but every President up to and including Obama and Trump have been obsequious servants of the House of Saud. If you want to take the moral high ground by blaming Trump you obviously have no conception of history. Your cushy way of life has been paved, in part, by US support of these midEast butchers for the last 100 years.