Sir Paul McCartney and Heather Mills will meet today to hammer out a deal in the most celebrated – and potentially most costly divorce battle in British legal history.

The couple and their lawyers will meet for a secret hearing, away from the immediate precincts of the Royal Courts of Justice, to try to agree a final settlement.

Lawyers say that the deal should be between £25 to £30 million but there was speculation last night it will outstrip the £48 million that insurance broker John Charman, 53, was ordered to pay to his former wife Beverley in May, in the biggest contested divorce settlement to date.

The case number is listed for 10.30am in the High Court Family Division under “Unassigned Cases”.

The judge hearing the case is Mr Justice Coleridge. If he fails to “bang heads together” he will disqualify himself from the case and it will go to a costly and public trial in March, before Mr Justice Bennett.

Under what is called a “financial dispute resolution” hearing, both sides will have to put all of their offers of settlement on the table.

The judge will indicate, within a range, what he thinks a court would order. In 90 per cent of such hearings, the parties agree to settle, saving the costs of a trial.

Some lawyers believe that there will be a settlement, with Sir Paul agreeing to increase his offer from his estimated £825 million fortune.

But others point out that there are several “egos” involved – those of the parties and the lawyers; and they say that a deal may be difficult to achieve.

Sir Paul and Ms Mills, who have a four-year-old daughter, Beatrice, announced last May that they were ending their four-year marriage.

The former Beatle, who is 65, faces a total payout approaching £70 million to provide for Ms Mills, 39, and their child, according to specialists.

When the couple announced their split, Sir Paul denied statements that his wife had married him for money and said the parting was amicable.

Subsequent spats in the courts did not support this.

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