Mark, 26, is said to have proposed to Michelle, also 26, on Friday night (6 September) while visiting the holiday destination where they had their first kiss.
His TOWIE star sister Jessica confirmed the news via Twitter, writing: "So pleased I can now express my congratulations about Mark & Michelle being engaged. So happy for them. Amazing couple, love them both lots."
According to The Mirror, the couple - who got together nine months ago - are now planning a lavish wedding for next summer.
A source told the newspaper that Mark designed a "monster rock" engagement ring himself, adding: "Both are blissfully in love and Michelle is utterly made-up."
Coronation Street star Michelle was spotted landing in the UK with Mark yesterday, however her wedding finger was bare.
Reveal has contacted the couple's reps for a comment. They have not mentioned the rumours on Twitter, however this morning Mark tweeted: "Just woke up in the UK from such an amazing holiday at the Atlantis in Dubai."
Both Michelle and Mark have been engaged before. In June, Michelle accepted a proposal from The Wanted's Max George after he got down on one knee at her birthday party.
However, the actress broke things off with Max after he allegedly cheated on her with his ex-girlfriend Bobbi Aney.
Mark, meanwhile, proposed to his former long-term girlfriend and fellow TOWIE star Lauren Goodger in front of the cameras in March 2011. Their rocky 10-year relationship ended just months later.
Mark and Michelle got together in January while in Dubai with friends and their romance has gone from strength to strength, despite their busy work schedules.
Last month, Michelle was pictured with Mark and his sister Jessica while at their little sister Natalya's 13th birthday party.
Michelle Keegan and Mark Wright: Their relationship in pictures:
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