The 38-year-old was expected to return to the UK last month having served 18 months of a two-year sentence for financial misappropriation.
But he has now been further detained after his former employer, investment bank Gulf Finance House (GFH), complained about remarks allegedly made on Twitter.
A spokesman for Mr Haigh said: “David maintains, as he has done since he was tricked into travelling to Dubai from the UK, that he is an innocent man who is being held in breach of basic human rights.
“Other than that he can say nothing while he remains in jail in Dubai.”
Mr Haigh, who was a director at United for just over a year in 2013-14 after leading GFH Capital’s negotiations to acquire the club, was originally arrested in Dubai on May 18 last year.
He was initially detained without charge for 14 months and had his worldwide assets frozen before being convicted in August this year of misappropriating items of monetary value from a position of trust from his former Dubai-based employer.
He was sentenced to two years in prison – the majority of which he had already served – but is reportedly considering seeking a retrial of his criminal conviction.
GFH is said to have complained about the alleged Twitter slander shortly before Mr Haigh’s expected release last month.
The complaint is believed to relate to messages from his official account, which is currently being managed on his behalf.
Mr Haigh is not thought to have been charged with the offence, but has appeared in court where he denied wrongdoing.
He says he could not have committed the alleged Twitter offence, which dates back to March, because he was in custody at the time.
According to the BBC, when asked if he sent the tweets in question from his @haighdavid account, he said: “Absolutely not. I was held in a jail in Dubai.”
He insisted he did not have access to a computer.
Mr Haigh felt “scared, frightened and worried”, the BBC said.
The matter has been adjourned until January 4. Mr Haigh’s solicitor said his client would not seek bail as he is already under a sentence of deportation and would be considered a flight risk.
The maximum penalty for cyber slander is three years in prison and a fine of up to £5,500.
A spokesman for GFH Capital said it would not comment at this time. The authorities in Dubai have also yet to comment.