JetBlue Airways CEO Joanna Geraghty said on Monday the company's partnership with United Airlines would not lead to a merger between the two carriers.

The two companies last week announced a collaboration that allows travelers to book flights on both carriers' websites, while interchangeably earning and using points in their frequent flyer programs.

"We've spent a lot of time with the Department of Justice over the last five years, and we're playing it safe," Geraghty said.