Megan, 24, and Brian, 36, called off their first engagement in February 2009 after five years together, but the screen beauty insists she doesn't consider it a new betrothal.
She added: "It's really not a re-engagement. It's just the same engagement and for some reason it's now news."
Following the announcement, speculation is now rife as to what sort of ceremony the couple may have, with Megan previously insisting their nuptials would be a private affair.
She said: "It's not going to be a big wedding. I'm not one of those girls - if it happens, it will be very low-key and quick and unplanned."
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