Coleen Rooney has launched legal action against Rebekah Vardy's agent after Whatsapp messages were read out in court.
According to Mrs Rooney's written case, messages exchanged between Mrs Vardy and Ms Watt in January 2019 showed the pair discussing a post on Mrs Rooney's private Instagram where her car had been damaged.
Mrs Vardy told Ms Watt she "would love to leak those stories x".
READ MORE: Every WhatsApp message exchanged over 'Wagatha Christie' row
Mrs Rooney's barrister David Sherborne claimed Ms Watt was later responsible for the leak of the story to a newspaper, with Mrs Vardy's approval.
Days after the story about her car was published in The S*n, Mrs Rooney posted a tweet saying it was "sad" someone who followed her was "betraying" her.
While discussing the tweet in a private WhatsApp conversation, Ms Watt told Mrs Vardy "It wasn't someone she trusted. It was me", in a message accompanied by a laughing emoji.
Mrs Rooney is now bringing a claim against Ms Watt for misuse of private information and is asking for it to be joined to the libel case.
Mrs Vardy's lawyers have opposed the application to add the claim against Ms Watt.
In written arguments, Mrs Vardy's barrister Hugh Tomlinson QC said: "If the defendant had genuinely wished to bring a misuse of private information claim against Ms Watt in order to vindicate her rights this claim could have been brought 15 months ago.
Ian Helme, for Ms Watt, also opposed the application and previously said she has given "clear and consistent" denials against the claim for misuse of private information.
Mr Sherborne told the court that if Mrs Vardy wins her claim on the basis that she was not the person who leaked the information, then Mrs Rooney will be left without "vindication" unless she is able to bring the claim against Ms Watt as part of the same case.
He also said that while Mrs Rooney's lawyers wanted further information from the WhatsApp messages between Mrs Vardy and Ms Watt, Ms Watt's phone had fallen into the sea after a boat she was on hit a wave, shortly after the last hearing.
He said: "(It was) most unfortunate, because it was only a short time after the court ordered that the phone should be specifically searched."
Discussing the lost phone on Wednesday, Mr Tomlinson said: "That is what happened. Mrs Vardy was not present when that happened. She (Ms Watt) was on holiday, she lost her phone."
Rebekah Vardy's lawyer has also hit back at claims she sent "abusive" messages about Coleen Rooney.
At the start of a preliminary hearing on Tuesday, the High Court heard that WhatsApp messages between Mrs Vardy and her agent and friend Caroline Watt had been disclosed to Mrs Rooney's legal team.
On Wednesday, Mr Tomlinson said a text in which she referred to someone as a "nasty b***h" was not about Mrs Rooney.
He said: "This is not a passage about Mrs Rooney, it is a passage about someone else."
Mr Tomlinson previously told the court that the messages referred to by Mr Sherborne, which were said to "reveal that Mrs Vardy and Ms Watt are responsible for the leaking", were "selective", and said parts of the exchanges which were left out had "precisely the opposite effect".
During Tuesday's hearing, the barrister quoted messages from Mrs Vardy to Ms Watt in which she said she was "offended" that Mrs Rooney thought she was the person who had leaked the information.
He added: "If one reads these messages in full, what one sees is that Mrs Vardy expresses shock at being accused and she is here communicating with the person that Mr Sherborne says is her co-conspirator.
"These are obviously candid personal messages, and if she was really concerned - 'Oh, this is terrible, we have been found out' - then it would have been completely different."
The trial is due to begin in early May but is likely to be delayed.
The hearing before Mrs Justice Steyn is due to finish on Wednesday.
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