Bristol Palin calls it quits with Levi Johnston

Teen mom Bristol Palin has broken off her engagement to Levi Johnston for a second time — less than a month after telling the world she planned to marry the father of her young son.

The 19-year-old daughter of politician Sarah Palin was quoted on Tuesday as telling People magazine "It's over. I broke up with him."

She said her on-again, off-again relationship with Johnston, 20, soured on July 14 — the day the couple announced in rival celebrity magazine Us Weekly that they had secretly become engaged again and planned to marry soon.

In an interview with People, Palin said Johnston told her that same evening he might have fathered a baby with another teenage girl. The girl has since denied Johnston is the father.

Bristol Palin's pregnancy and first engagement to Johnston were revealed during her mother's Republican vice-presidential campaign in 2008, providing some awkward moments for the staunch conservative who supports the teaching of abstinence in schools as a form of sex education.

The young couple broke up later in 2008, and Johnston went on to pose nude for Playgirl magazine and publicly criticized the Palin family. He later apologized for his comments and admitted some of what he said was untrue.

Bristol Palin said last month that her family was not supportive of their re-engagement. On Tuesday, Palin said she and Johnston had seen each other only once in three weeks.

"The final straw was him flying to Hollywood for what he told me was to see some hunting show but (I) come to find out it was that music video mocking my family," she says. "He's just obsessed with the limelight and I got played."

Sarah Palin, who is widely thought to be planning a presidential run in 2012, said in a statement to People on Tuesday that she hoped Bristol would move forward in her life "with her same forgiving, gracious, optimistic spirit, but from henceforth she'll know to trust but verify.

"Bristol is strong, she is independent, and she knows what is right for her son," Sarah Palin said.

People magazine's issue with the Palin interview hits newsstands on Friday.