The two departed London's Heathrow on Tuesday night as Cheryl hugged her assistant goodbye and hopped on the plane.
"[The holiday] was a complete surprise to Cheryl and she couldn't believe he had gone to so much trouble organising it," claims a source. "She was told to take her passport and all would be revealed at the airport."
Derek's stepfather, Aaron Nelson, said:
"They are going somewhere very exotic, very picturesque and it will be a nice break for them.
It will be one of those dream romantic holidays that you take when you are just starting out on a relationship. Derek is totally in love with the girl and wants to spend as much time as he can with her."
Although it will be a short trip! Cheryl needs to get back for more X Factor auditions next week.
Have fun, you two!
[Image via WENN.]