U.S. President Donald Trump has built a business empire spanning real estate, casinos and entertainment. His family’s growing crypto dealings are now facing mounting criticism over conflicts of interest and foreign influence.

A top United Arab Emirates official holds a stake in the family’s latest venture: a planned crypto bank now drawing scrutiny over foreign ties to a sitting President. The Wall Street Journal has reported that Sheikh Tahnoon bin Zayed al Nahyan, the UAE’s national security adviser, and his co-investors own a major stake in the company behind that bank.

Earlier this month, the Office of the Comptroller of the Currency gave conditional approval to World Liberty Financial, backed by Mr. Trump’s family and close…