Bristol Palin Pulls Out of Engagement to Levi

8/3/2010 5:55 PM PDT

Bristol Palin Pulls Out of Engagement to Levi

Just days after announcing their engagement to the world -- Bristol Palin claims she has officially broken things off with Levi Johnston after Levi told her that he may have knocked up another woman.

Bristol told that Levi -- father of their 19-month-old son Tripp -- told her about his scumbaggary on the same day they announced their engagement ... but that wasn't the final straw.

Bristol claims she decided to pull the trigger on the relationship after Levi lied about a recent trip to L.A. ... when he said he was traveling for a hunting show ... and instead shot a music video mocking the Palin family.

As for Bristol's mom -- Sarah told, "Bristol is strong, she is independent, and she knows what is right for her son."