Mitchell, who plays Romeo Smith to Breeds's Ruby Buckton in the Australian soap, was rumoured to have proposed to his girlfriend of two years after they were spotted on Hayman Island earlier this week.
However, the duo later insisted to the Herald Sun that they were just enjoying a holiday to celebrate Mitchell's birthday while they had a break in production from Home and Away.
In October last year, Mitchell and Breeds were believed to be considering marriage and moving in together after they were seen looking at an apartment for sale in Sydney.
Mitchell has previously said that they "like to have arguments" about "anything and everything", while Breeds said: "We do have little tiffs. I push his buttons. We're not perfect - we're just a healthy, normal couple."
Mitchell's character Romeo once cheated on his on-screen wife with Ruby. After the scenes were filmed, they said that it was "fun to do" but insisted that they didn't want to become more permanent "love interests on the show".
> 'Home and Away' Romeo, Indi facing break-up
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