Damages on top could easily push the total cost for the losing wag to over £2m.
The two sides have drawn up an estimate of their costs ahead of a private ‘budget and timetable’ hearing by telephone on Tuesday.
The figures put into court by lawyers acting for the warring parties underline the high stakes in the battle of the wags - as well as highlighting the eye-watering fees charged by defamation lawyers..
Rebekah’s lawyers estimate their costs at the end of a trial would be nearly £1.1m, with bills of more than £400,000 already incurred.
The loser of the 'Wagatha Christie' high court battle could face legal bills of more than £1.6m as Rebekah Vardy's (pictured) legal team have estimated their costs alone could reach £1.1million
Coleen’s camp have assessed their costs at just over £500,000 in total, with around £200,000 incurred already.
Whichever side lost in the event of a trial would most likely have to meet the other’s costs as well as their own. Adding in any damages could well take the loser’s bill to over £2 million.
Last month, MailOnline revealed Coleen’s 11th-hour peace offer to Rebekah, suggesting that if Rebekah, 39, accepted her Instagram account was the source of leaked stories to the press, then Coleen would accept her assurances that she personally knew nothing about the leaks.
Sources have repeatedly indicated that Coleen, 34 – married to footballer Wayne Rooney – has always found the cost of litigation 'grotesque' in the current circumstances, believing the money could be better spent elsewhere.
That is why she has repeatedly offered to settle – previously offering to 'drop hands' – a lawyers' term meaning both sides pay their own legal costs – with each of the footballers' wives also donating to charity.
It is understood that the latest offer was made in correspondence from Coleen's lawyers to the Vardy side before a failed mediation hearing between the two parties earlier this month.
Coleen Rooney's team have said their costs could reach £500,000 if the case should go to trial
Former Dancing On Ice contestant Rebekah, who is married to footballer Jamie Vardy, has rejected all Coleen's offers, meaning that the libel action she brought against Coleen looks set to go to a full court hearing.
Coleen’s side lost an intermediary 'meanings hearing' in November.
At that round of the case, the dispute was over the wording of Coleen's social media post, which she put up for her 1.2 million Twitter followers and 885,000 Instagram followers to see last year.
Rooney named the culprit of the leaks as 'Rebekah Vardy's account', and her lawyers argued that she hadn't implied Rebekah herself was guilty – and instead the culprit could have been anyone with access to her Instagram account.
But Judge Mark Warby ruled against this, saying the post looked as though it was putting the blame solely on Vardy.
He ruled that Coleen's post 'clearly identified' Rebekah as being 'guilty of the serious and consistent breach of trust'.
Vardy and Rooney celebrate England's win against Wales at Stade Bollaert-Delelis in France
The judge said an ordinary reader would not take the word 'account' to 'indicate that she remains in doubt about who the wrongdoer was'.
Under the law of libel, that means the onus was now on Coleen's side to prove that not only did the posts come from Rebekah's account, but also that she was responsible.
Rebekah launched her £1 million High Court libel action after Coleen accused her in an October 2019 Instagram post of being the source of leaks to the media.
The long-running feud between the high-profile WAGS erupted after Coleen revealed that she had set a trap to see who was responsible for the leaks, which earned her the nickname 'Wagatha Christie'.
Soon after, Rebekah took to social media to deny being the leaker after Coleen's post went viral.
Last February, Rebekah broke down on ITV's Loose Women, saying the feud was 'one of the worst things I had to deal with apart from being abused when I was younger'.
Last June, it emerged that Rebekah had launched a case to sue Coleen for £1 million.
In October 2020, Coleen 'doubled down' by filing her 55-page defence and sharing images of the Instagram posts she alleged Rebekah leaked.
The following month, Rebekah won the first round of her High Court libel battle at the 'meanings hearing'
Earlier this month, the pair attended a court-ordered mediation session on Zoom, their first meeting for years.
Zoom proceedings began with both sides reading out a statement and then breaking off into separate virtual rooms as the mediator spoke to them and their legal representatives independently.
Former columnist Coleen reportedly tried to reach out to brunette Rebekah after another round of failed talks to avoid a costly legal battle.
However, it's thought that she saw the mediation as a 'waste of time' as TV star Becky continues to demand she apologise for her fierce accusation.
How Wagatha Christie row exploded from one Instagram post... to the High Court
October 9, 2019: Coleen Rooney accuses Rebekah Vardy of 'leaking stories about her' to The Sun.
Coleen famously wrote: 'I have saved and screenshotted all the original stories which clearly show just one person has viewed them. It's ................ Rebekah Vardy's account.'
October 9, 2019: Rebekah takes to her social media to deny being the leaker as Coleen's post goes viral, while a Sun spokesman refuses to comment on the source of their stories.
February 13, 2020: Rebekah breaks down on ITV's Loose Women, saying the spat was 'one of the worst things I had to deal with apart from being abused when I was younger'.
June 22, 2020: It emerges that Rebekah has launched a case to sue Coleen for £1m.
October 02, 2020: Coleen files her 55-page defence and shares images of the Instagram posts she alleges Rebekah leaked.
November 20, 2020 Rebekah wins the first round of her High Court libel battle.
January 18, 2021: Reporters emerge that the pair will be holding a mediation session over Zoom.
February 4: The pair attend the mediation session, in their first meeting for years.