Miley Cyrus: 'I'm Not Engaged' To Liam Hemsworth

Liam Hemsworth, Miley Cyrus and her ring (inset) -- Getty Images

Miley Cyrus and Liam Hemsworth made headlines late last week after the singer Tweeted a photo of her left hand rocking a hefty diamond sparkler - but now the 19-year-old star says she not engaged to the 22-year-old "The Hunger Games" star.

Speculation began when the "Party in the U.S.A." singer Tweeted a photo of her left hand (featuring the ring) last week with the caption, "I am sooo obsessed with @jennahipp nail foundations!"

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Miley and Liam did nothing to squelch engagement rumors as they stepped out together for Muhammad Ali's Celebrity Fight Night XVVIII in Phoenix, Ariz., on Saturday evening, where Miley posed for red carpet photos with the rock prominently displayed on her wedding ring finger.

Despite the ring on Miley's finger, the star slammed the rumors on Monday.

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"I'm not engaged. I've worn this same ring on this finger since November! People just wanna find something to tal about! It's a topaz people!," she wrote on Twitter.

The couple has been dating on-and-off since 2009 and have a puppy (English bulldog Ziggy) together.

Miley recently sang her Australian boyfriend's praises at "The Hunger Games'" Los Angeles Premiere, where she told Access Hollywood she was thrilled for Liam's recent success.

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"I'm so excited. This year has just been amazing and Liam deserves it. There's so many people out there that I think don't even know what he's capable of and I can't wait until people see it!" Miley told Access' Shaun Robinson at the movie's premiere earlier this month.

"He loves making movies and it's not about any of the fame or anything else other than he just loves filmmaking," she added.

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