The former banker used private bookmakers registered on the Caribbean island of Curacao for the bet at odds of 37/20 — meaning he could get a $15 million payout, sources told the Sun.

The mystery gambler confidently went all-in after consulting with “Trump camp insiders,” according to the report.

“Word of this bet has done the rounds and we think it’s the biggest ever made on politics,” one betting industry source told the UK paper.