DETAILS of the divorce settlement of the most closely scrutinised royal marriage of all time were announced yesterday, ending months of negotiation between the lawyers for the Prince and Princess of Wales.

Princes William and Harry spent last night at their ``saddened'' mother's side, following the announcement that Charles and Diana will start divorce proceedings on Monday.

Although financial details are confidential, it is understood that in the clean-break settlement, the prince is giving the princess a one-off payment of at least #17m.

Although she will keep the title of Diana, Princess of Wales, she will lose the style Her Royal Highness.

The divorce hearing is listed to take place in front of the same Senior District Judge, Gerald Angel, who presided over the Duke and Duchess of York's decree nisi hearing.

Their 15-year marriage will end on August 28.

A statement issued by the lawyers for the prince and princess said the estranged couple had agreed terms for divorce after ``amicable'' negotiations.

Royal sources said last night that the princess was closeted with her sons at Kensington Palace as she prepared to face up to life as a single woman.

Close friends believe she will spend the weekend coming to terms with her new role in life and may decide to take the boys away with her on holiday next week.

Any firm decisions about her future public role are unlikely to be announced before the autumn. The princess has, however, agreed that any representational role, at home or abroad, will be undertaken with the permission of the sovereign.

At present, this means that the Queen must be consulted, and in future, should the Prince of Wales become king, she would have to seek her ex-husband's go-ahead.

It is understood that there would be no objection to the princess continuing her present role of raising funds for charity, in Britain and abroad.

A palace spokesman said: ``The princess's ambassadorial role is one that has attracted a lot of interest. The princess already has an international role in the context of some of her charities and it would be for her to decide how that is carried forward. If the princess wants further advice, it would be readily given by Buckingham Palace and, where relevant, by the Government of the day.''

This weekend, however, she will be reflecting on a settlement, thought to include a cash pay-off in the region of #17m (providing the princess with an annual net income of at least #500,000) and equal access to the children. In addition, the princess will receive an annual payment of about #400,000 to run her private office.

It is understood that the prince balked at a request from Diana that he should sign a confidentiality or ``gagging'' clause in the same way as she was being required to do. The prince considered that his word not to divulge details of his life with his ex-wife was good enough.

Buckingham Palace said yesterday that although the princess will no longer be addressed as Her Royal Highness, the Queen and the Prince of Wales have made it clear that she will be ``regarded'' as a member of the royal family - a move in contrast to the status accorded the divorced Duchess of York.

A palace spokesman said: ``This agreement recognises, on the one hand, that the princess took the style HRH on marriage and therefore would be expected to give it up on divorce. And, on the other hand, it recognises she remains in a unique position as the mother of Prince William.''

It is most likely that the princess will be invited to accompany the young Prince William to royal and national occasions. When William is 18, he will be regarded as an adult and is likely to carry out official engagements on his own.

A spokesman for Burke's Peerage described the announcement that the princess was to lose her HRH title as ``without precedent''.

``The British monarchy is in danger of being considered untraditional and mean in its decision to strip the ex-Princess of Wales from the designation which is rightfully hers,'' a statement from Mr Harold Brooks-Baker, publishing director of the publication, said.

``It is not possible for the mother of a future monarch to be deprived of `HRH' without creating negative public reaction throughout the Commonwealth. It is anticipated that most world leaders as well as the people they represent will take a very dim view of Buckingham Palace's announcement this afternoon," added Mr Brooks-Baker.

The final negotiations to agree the divorce package were carried out this week, although it is understood there were protracted discussions on whether the princess should lose or retain the style HRH.

A palace spokesman said: ``It is entirely up to individuals whether they wish to bow or curtsey or which forms of address they use. The form of address Ma'am is perfectly acceptable to the princess.''

If the Prince of Wales abides by his declared intention not to remarry after divorce, the Princess Royal could play a prominent role at the side of the future King Charles.

No mention in the official announcements has been made concerning the princess's position should she remarry. Buckingham Palace declined to comment, saying the matter was hypothetical. However, it is certain that a clause has been written into the divorce package which would most likely strip the princess of many of the agreed benefits should she marry again.

The princess will keep jewellery and family heirlooms given to her as Princess of Wales. It is likely that jewels would be passed on, should they marry, to the wives of Prince William and Prince Harry.

Taxpayers' money will be involved in future spending on behalf of the princess. The external maintenance of her Kensington Palace apartments will be paid for by Government grant-in-aid, in other words, from the public purse.

Use of Royal Squadron flights - and of the Royal Train, which is also still available to the princess - would incur further cost to the taxpayer, as would her police protection.

Finance of her private office will, however, come directly from the Prince of Wales, out of his income derived from the Duchy of Cornwall.

News of the royal divorce was greeted with a mixture of sadness and relief.

Lambeth Palace said in a statement that the Archbishop of Canterbury was ``pleased that the inevitable strain and uncertainty which accompany negotiations of this kind are now at an end.''

It added: ``Despite the obvious sadness of a divorce, he hopes this settlement will help ease the burden of past problems and enable all concerned to find renewed life and hope for the future. He gladly pledges whatever help and support he can give to all members of the family.''

Environmentalist Jonathan Porritt, a friend of the prince's, told BBC1's Nine O'Clock News the divorce would come as a relief to Charles. ``This kind of experience, I think, is difficult for anybody and no less for being the Prince of Wales than it would be for anybody else,'' he said.

``It's particularly true, I think, that he wants to contribute so much to the activities of this country and that more people will come to value that contribution once all the hubbub and fuss about his marriage and divorce is behind him.''