Price was spotted wearing a diamond band on her wedding finger at a book signing last month, sparking rumours that she will marry the Argentinian model.
A spokesperson for Price has already explained that there is "no engagement" and claimed that "the ring just happened to fit that finger".
Price has now added on Twitter: "I'm NOT engaged. (sic)
"If you look at old pics and new I ALWAYS wear rings on wedding finger and same on other hand and always will."
Price has previously been married to singer Peter Andre and cage fighter Alex Reid. She started dating Penna in March and Penna got the name "Katie" tattooed on his arm last month.
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