mariah carey
Singer Mariah Carey poses at the Los Angeles premiere of "Hercules" in Hollywood, California July 23, 2014. Reuters/Danny Moloshok

Mariah Carey and director Brett Ratner travelled to the Caribbean on Friday for their birthdays, giving rise to speculation that the two are dating. A source told Radar Online that the 45-year-old and her longtime friend are “a hot couple.”

“Their relationship has progressed in recent weeks and is now very serious,” the source reportedly said. Carey and Ratner have reportedly become close since the former split with her husband Nick Cannon in June 2014. Since then, Cannon and Carey have been living separately and are waiting for their divorce to be finalized.

Carey turned 45 on Friday, while Ratner will celebrate his 46th birthday on Saturday.

The source also reportedly claimed that the duo boarded Australian billionaire James Packer's private jet for their holiday, and also booked a $70 million yacht.

On Sunday, Ratner and Carey were spotted having dinner with Courtney Love in West Hollywood.

A source told E! News last week that Carey’s estranged husband is currently dating model Jessica White, and that she has even met the former couple's twins -- Monroe and Moroccan. However, the source added that Cannon and White are maintaining that they will remain “purely just friends” until the former is separated from Carey.