The London-born Osbournes star took to Twitter on Tuesday to reveal that he recently completed the US naturalisation process.
"Woah. I just became a US citizen. Don't worry England I'm still British," Osbourne jokingly tweeted.
Jack also shared a congratulatory message he received from his father Ozzy Osbourne, writing: "This is what @OfficialOzzy texted me- 'So I guess u have become an American oh well just as long as you r happy I still love you dearly' (sic)."
The 26-year-old Jack also revealed that he's expecting more happy news as his fiancée Lisa Stelly could give birth to the couple's first child In the next few days.
The pair announced their engagement in September 2011, with news of Stelly's pregnancy coming one month later.
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