Prince Andrew believed he would easily beat Virginia Giuffre's sex allegations against him but his mood has changed, sources claim.
It's said the Duke of York is no longer convinced after the High Court announced on Monday it will act to serve US civil case papers on him.
The prince, who vehemently denies the claims, is reportedly bracing himself for a legal battle that he fears could go on for years and cost millions of pounds, writes The Mirror.
Ms Giuffre has accused Andrew, 61, of forcing her to sleep with him on three occasions when she was 17 and a minor.
Royal insiders have told the paper the prince's confidence on the case collapsing has shifted, whereas he hoped he could return to royal duties.
One source claimed: “He’s not been his usual blasé self, acting like everything is in hand.
“The issue has suddenly become very pressing and there is a distinct tension in the air.
“There has been a dramatic shift in mood and the reality that this could not only go on for many months, if not years, as well as costing potentially millions of pounds is very real.”
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Another insider added: “The stark reality is that the Duke and his team need to face the fact they need to address this.”
Legal experts have predicted Ms Guiffre could be awarded around £14million if she wins.
Her lawyer David Boies said: “We are hopeful that Prince Andrew will now stop trying to evade and delay facing his accuser in court.
“The bottom line is Andrew is being served. He cannot refuse.”
The US judge refused to unseal a document the prince's lawyers' claim would invalidate Ms Guiffre's claim.
It's alleged the document, signed by his accuser, prevents her from suing.
Andrew's legal team will now have to make a request for a copy and that would mean accepting he has been served the lawsuit.
The High Court will begin making arrangements for service of proceedings on the Duke, giving details of the claims made against him.
Once served, his lawyers would have 21 days to respond.
An American Judge dismissed claims earlier this week that the Duke could not respond to the suit as he had not received the documents, despite them being left with a policeman at his Windsor home.
Lewis A Kaplan has listed the case for a further hearing on October 17.
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