NEW rules on changes to royal titles after divorce were announced yesterday by Buckingham Palace.

But although the proclamation on the authority of the Queen starts with the historic wording ``The Queen has been pleased . . . to declare'', the palace made it clear that no snub to Diana, Princess of Wales is intended by the change or its timing.

The changes, announced in the form of letters patent, are intended to avoid future debates like those which arose over this year's two royal divorces - whether the divorced wives should keep the style of ``Her Royal Highness''.

Like the Duchess of York before her, Diana accepted the loss of the HRH before her name, but only after months of often public debate.

Yesterday she attended her first engagement as Diana, Princess of Wales.

The new rules make it clear that in future, divorced wives of male descendants of the sovereign will not be entitled to use the Royal Highness title.

The letters patent will appear tomorrow's issue of the London Gazette, which is effectively the official Government newspaper of record for a variety of announcements.

Its release yesterday, just hours after the decree absolute in the Waleses' divorce, was decided because legal preparation work had been concluded and it was felt that it was more appropriate for it to coincide with the divorce rather than delay and make an entirely separate announcement, said a palace spokesman.

The Queen and her advisers decided the new statement was needed because the issue had never been addressed in previous letters patent on the HRH status, dating back from the reign of Queen Victoria.

Just as those letters patent were still in force, so it was intended that yesterday's changes would serve for future generations, with no-one named in the new declaration.

Until this year no members of the royal family had been faced with the need to give up titles or styles on divorce.

When the problem was first considered, at the time of the Yorks' divorce, discussions about the possible future use of HRH by Diana were continuing.

It was not possible to make a definitive statement until those discussions were completed and all aspects of the situation could be considered, the palace spokeswoman said.

Letters patent are one of the ways in which the sovereign's will is expressed, for instance to announce Royal Assent to parliamentary Bills.

The wording follows a traditional form which includes the use of the ancient concept of the sovereign being ``pleased'' to announce.

It says: ``The Queen has been pleased by Letters Patent under the Great Seal of the Realm dated 21st August 1996 to declare that a former wife (other than a widow until she shall remarry) of a son of a Sovereign of these Realms, of a son of a son of a Sovereign and of the eldest living son of the eldest son of the Prince of Wales shall not be entitled to hold and enjoy the style, title or attribute of Royal Highness.''

The Queen signs a warrant directing the issue of letters patent, which are prepared in the Crown Office, within the Lord Chancellor's Department.

The Great Seal of the Realm is affixed, and the document is then published in the London Gazette, which is circulated to government departments and embassies.

The present rules about the use of HRH were laid down on the orders of King George V nearly eight decades ago, modifying previous letters patent issued by Queen Victoria in 1861.

The 1917 rules are that HRH be confined to children of the sovereign, the children of the sons of the sovereign, and the eldest living son of the eldest son of the Prince of Wales.

Yesterday's rules apply to the former wives of those offspring.