LONDON -- Prince Charles' attack earlier this month on a major development project around St. Paul's Cathedral was just the latest in his relentless campaign against the modern buildings that he maintains have disfigured London since World War II.

Perhaps Britain's most powerful and acerbic architectural critic, Charles has no training in architecture, but he is a man who knows what he likes and maintains he speaks for an outraged majority.

It has become commonplace among Londoners to say that developers have done more damage to the city than German bombers did during the war. The developers have filled London's streets with boxlike structures that to many appear ill suited to their surroundings and often are constructed of shoddy materials.

Charles made these complaints earlier this month when he addressed the Corporation of London's planning committee.

"You have to give this much to the Luftwaffe -- when it knocked down our buildings, it didn't replace them with anything more offensive than rubble," he said. "We did that." The Luftwaffe was the German air force.

The prince's latest ire was directed at a scheme to tear down modern office buildings to the north of St. Paul's Cathedral and replace them with a complex containing 1 million square feet of office space.

St. Paul's, designed by Sir Christopher Wren in the late 17th century, is the third largest church in Christendom, and its 365-foot-high dome is the centerpiece of the City, the London financial district.

Charles calls it "our greatest national monument" and laments that over 15 years in the 1960s and 1970s architects and developers combined to hem it in with high-rise buildings and to wreck the London skyline, of which it is a principal adornment.

The development he recently attacked is planned for Paternoster Square, beside the cathedral. The site was bought last year by Stuart Lipton, a leading London developer, who then organized an architectural competition in which such leading figures as Richard Rogers, Norman Foster and James Stirling participated.

Charles looked over all eight competition entries and found them lacking. But the design contract was awarded last August to Arup Associates, a London firm whose plan reportedly calls for classically influenced buildings forming a ring of office blocks limited to a height of 110 feet.

Charles said the French had built some "pretty awful" tower blocks, but it was not possible to imagine them doing so around the Cathedral of Notre Dame.

He said he would like to see the medieval street plan of prewar Paternoster reconstructed. His preference was for sheltered arcades, courtyards, a public square and small shops and businesses at ground level, all designed to enhance the cathedral rather than obscure it.

It remains to be seen what effect his remarks will have. But architects have learned that a word from Charles sometimes is sufficient to kill a project and send the offending architectural firm's fortunes into a tailspin.

In 1984 he denounced one developer's plan to implement a design by the late Ludwig Mies van der Rohe for a 290-foot tower alongside the classical fac ades of Mansion House Square. He said the building would be "yet another glass stump better suited to downtown Chicago than to the City of London." The building was never erected.

At the same time, Charles attacked a proposed modernistic extension to the National Gallery as "a kind of vast municipal fire station ... like a monstrous carbuncle on the face of a much-loved and elegant friend." The design was withdrawn and another firm chosen to develop a new one.

In his latest speech, Charles said, "Large numbers of us in this country are fed up with being talked down to and dictated to by the existing planning, architectural and development establishment." A recent survey found that 87 percent of Britons support him for speaking out about architecture.

In response to his latest comments, Lord St. John of Fawsley, chairman of the Royal Fine Arts Commission, said, "Prince Charles is doing a magnificent job to raise the esthetic standards in a culturally deprived country that has never thought art nor architecture important."

Rod Hackney, president of the Royal Institute of British Architects, also supports Charles. But past president Michael Manser indicated he was irked at him and recently commented that "architects are getting fed up with the prince's interference."

Charles' speech was followed, coincidentally, by an announcement from Lloyd's of London, the insurance market, that it plans to appoint a firm to correct problems in its new $350 million headquarters building in the City designed by Richard Rogers, best known for his design of the Pompidou Centre in Paris.

A survey of insurance people who work there found that three-quarters believe it is worse than their old building across the street. They complained about the design of trading floors, poor lighting, slow elevators and other features.