Reality TV star Heidi Montag has taken legal action regarding her separation from husband Spencer Pratt.

ET has obtained court documents filed by Montag Tuesday in Santa Monica, CA, in which she is seeking legal separation from Pratt. She cites irreconcilable differences as the reason for the separation.

The couple has been married since April 25, 2009. Click here to read the documents.

Last week, Montag told "I needed some alone time. There are so many lies out there about me and I just needed space -- even away from my husband."

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