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Britney Spears and her fiancé, Jason Trawick, will not be getting married and, instead, will be going "their separate ways."

"Jason and I have decided to call off our engagement. I'll always adore him and we will remain great friends," Spears said in a statement sent by her representative to ABC News.

The singer got engaged to her former agent in December 2011.

"As this chapter ends for us a new one begins," Trawick said in the statement. "I love and cherish her and her boys and we will be close forever."

The couple started dating in 2009.

Trawick told " Access Hollywood" in December 2011 that he got down on one knee to pop the question and Spears' sons, Sean Preston and Jayden James, witnessed the proposal.

But Spears' representative, Jeff Raymond, said they've now decided to be just friends.

"Britney Spears and Jason Trawick have mutually agreed to end their one-year engagement," Raymond said. "As two mature adults, they came to the difficult decision to go their separate ways while continuing to remain friends."

The news of the break-up came after Spears announced earlier today that she would not be returning as a judge on the TV show, "The X Factor."

"I've made the very difficult decision not to return for another season," Spears said in a prepared statement.

The reason: She wants to start making new music.

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Spears has been married twice.

Her first marriage - which ended in an annulment - was to a friend, Jason Alexander. Her second marriage was to Kevin Federline. That relationship ended in divorce in 2006.

On Friday, Trawick also resigned as co-conservator for the pop star, The Associated Press reported.

In April 2012, Trawick was named a co-conservator by a Los Angeles judge, according to People magazine.

Along with Spears' dad, Jamie Spears, Trawick had a say in the pop star's personal affairs but not in her financial affairs. Spears' dad continues to manage the latter.

A lawyer for Spears' father said the request was made by the singer. Jamie Spears has been his daughter's conservator since her emotional breakdown in February 2008.

ABC News' Sheila Marikar contributed to this report.