In 2008 Diageo entered into a three year distribution agreement for Zacapa rum with the option to take an equity stake in Zacapa at the end of the term.
A statement from Diageo said: "We have now reached an agreement and, subject to the usual closing conditions, Diageo will take a 50% controlling stake in Zacapa.
"No details of the transaction are being released but we can confirm that it meets Diageo's investment criterion and is economic profit positive in year three."