The head of Mexico’s Financial Intelligence Unit has resigned after huge amounts of cash were found on guests attending his foreign wedding, hosted in Guatemala.

Santiago Nieto was formerly responsible for overseeing Mexico's attempts to crack down on corruption and money laundering. Guatemalan authorities seized $35,000 in cash from a private jet carrying influential guests to the ceremony.

The money belonged to guest Juan Francisco Ealy Ortiz, president of newspaper El Universal, who claims it was to be used to pay for healthcare and had been fully declared.

However, n...