It is the most public and high-profile of divorce battles but yesterday the final phase began in private, with doors barred to press and public alike.

Sir Paul McCartney and Heather Mills arrived to dozens of photographers and an overhead helicopter at the Royal Courts of Justice in London to hammer out a financial deal.

But once inside the Gothic-revival labyrinth of courts in the Strand, the couple disappeared into Court 34 to do battle before Mr Justice Bennett. In the early part of the 20th century the High Court Family Division was called the Probate, Divorce and Admiralty and was nicknamed Wills, Wives and Wrecks. Not much has changed.

Both parties wore appropriately sober grey-striped suits, Sir Paul topping off his with a black-and-white knitted scarf draped casually around his neck. Miss Mills was wearing a grey-striped peplum jacket and matching skirt over a rose-pink blouse and mid-calf boots.

Sir Paul was accompanied by his heavyweight legal team led by Fiona Shackleton, a divorce lawyer who also acted for the Prince of Wales in his divorce from Diana, Princess of Wales. Miss Mills was supported, arms linked, by her sister and had a couple of bodyguards in tow.

The cost of future security is thought to be a key issue, with the former model pressing for a deal that includes what she says is needed for her protection and that of the couple’s three-year-old daughter, Beatrice.

Miss Mills, who has dispensed with lawyers for the five-day hearing, will be conducting her case herself, even, if necessary, interrogating Sir Paul.

She arrived well in advance of the hearing in a black Mercedes that came to rest in a disabled parking space in an area used by judges alongside the court complex.

Boxes and what looked like a projector screen were carried into her side of the court. Miss Mills has created a video in which she appears to be hounded by paparazzi and nearly caught up in a car crash and it is likely this was shown to the judge.

The two-minute production, Hunting Heather, is a mix of clips shot by her personal trainer, Ben Amigoni, 23. It is posted on her new website.

Sir Paul’s lawyers, by contrast, had trundled in boxes of documents. His former wife’s entourage used a different door a few yards away.

After attempts at a settlement foundered before Christmas, it will be up to the judge to hear evidence from both sides, look at offers and demands and decide what is a fair settlement.

It is believed that Sir Paul has offered a lump sum of £20 million, possibly with further annual payments of £2.5 million until the couple’s daughter, Beatrice, reaches 18.

But Miss Mills is thought to be pushing for a package worth upwards of £70 million or even £80 million, including payment of her estimated £2 million legal fees owed to her previous law firm, Mishcon de Reya.

The final figure may never be known unless either party goes to the Court of Appeal, when the details of their battle would be aired in public.

The hearing continues.

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