Prime Minister Tillman Thomas told a news conference Friday that he had ordered an investigation into the deal, which occurred before he took office.
The deed for the property shows that the government transferred property worth US$15 million to Hamilton "free from encumbrances" in exchange for using his image and name for the next four years, apparently to promote tourism.
Land transfer
However Hamilton's group did pay US$35 million for the Grenada Grand Beach Resort built on the property, according to a copy of the deed seen by The Associated Press.
The deed was signed July 7 of this year, a day before the general election.
The deal is controversial in part because Grenada's government owns nearly all beachfront land and leases it to developers for an annual fee. Some local journalists complained that taxpayers received no payment for transfer of the land.
Daniella Mitchell, who works for the local law firm listed in the deed, did not immediately return a call for comment.
Former prime minister Keith Mitchell told legislators Thursday that Hamilton's image would bring in millions of dollars in revenue. Hamilton has not done any promotional work so far.
Hamilton's grandfather lives in Grenada. (AP)