Miley Cyrus, Liam Hemsworth Miley Cyrus, Liam Hemsworth

Questions continue to swirl around are-they-or-aren't-they-engaged couple Miley Cyrus and Liam Hemsworth. Us Weekly reports that Hemsworth has called off their wedding following an intervention by his brothers, Thor star Chris Hemsworth and Luke Hemsworth.

"They are definitely over," an unnamed source told the magazine of their most recent split.

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This is just the latest report of trouble between Cyrus, 20, and Hemsworth, 23, who became engaged last June after dating on-and-off for three years. Cyrus has been spotted without her 3.5-carat engagement ring multiple times in recent months, during which time she also appeared at several events by herself.

When reports that she had split from Hemsworth first started in early March, Cyrus denied the breakup and said she was "sick of the lies" on Twitter. "I didn't call off my wedding. Taking a break from social media," she wrote. "My new music is gonna shut everyone up." Weeks later, she got a tattoo of Leonardo da Vinci's anatomical heart, courtesy of LA Ink star Kat Von D.

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Cyrus' new single, "We Can't Stop," comes out June 3.

Do you think these two lovebirds are really over? Or do you want them to make it work?