One of the world's most famous department stores today won a legal fight with fur trade protesters after complaining that families were "harassed" when pop star Lady Gaga visited to advertise perfume.

A High Court judge tightened restrictions on protests outside Harrods in Knightsbridge, London, after being told that demonstrators had caused a "nuisance" during Lady Gaga's appearance in October 2012.

Mr Justice Globe concluded that existing restrictions on protests did not provide "sufficient protection".

The judge issued a written ruling after a High Court hearing in London in May.

Harrods' bosses had complained about the behaviour of protesters during Lady Gaga's visit on October 7.

Mr Justice Globe said the star had visited the store to "advertise some perfumery".

"It is Harrods' case that the (protesters) positioned themselves at the front of the crowds with banners and placards, in and amongst families and children, causing a nuisance, annoyance and harassment to members of the public in attendance enjoying the event," said the judge.

"From statements, photographs and CCTV evidence, I have a very clear understanding of the nature of the event and what happened on this occasion."

He said Harrods had also complained about protesters' behaviour on Boxing Day 2012 - the first day of the store's winter sale.

The judge said anti-fur trade campaigners began demonstrations outside Harrods in 2005. Store bosses launched legal action shortly afterwards and court injunctions were subsequently issued, amended and extended.

He said exclusion zones and "specific protest areas" had been established but Harrods suggested that restrictions should be extended to a pedestrianised area in nearby Hans Crescent.

"Harrods have started to utilise to greater advantage the fully completed development of Hans Crescent," said the judge. "The existing order did not take into account its fully-completed state and its potential."

He added: "It has become a tourist hotspot likened to the area around Covent Garden. In conjunction with the Royal Borough of Kensington and Chelsea, the store is now organising more substantial events in the Hans Crescent area, which are drawing larger crowds to see what effectively is a show."

Mr Justice Globe, who said Lady Gaga arrived in Hans Crescent before going into Harrods, concluded that there had been a "change of circumstances".

"I am not satisfied that the existing order provides sufficient protection for the rights of the claimants, customers and the public to enjoy the facilities and events in the crescent," said the judge.

"I am equally satisfied that the rights of the (protesters) can be protected by ensuring that they can continue to assemble and protest outside the Hans Crescent area."

Harrods took legal action against animal rights campaigner Brendan McNally and the Coalition to Abolish the Fur Trade.

Mr Justice Globe said Mr McNally acted in person at the hearing and had "formulated intelligent and intelligible" submissions on behalf of protesters.

The judge said Mr McNally disagreed with the way protesters had been portrayed.

"He relies upon the fact that there have been no convictions of any protesters over the whole time of the order. He therefore argues that they have behaved responsibly and exercised their rights peacefully within the ambit of the current order," said Mr Justice Globe.

"He disputes the contentions of the claimants about the extent of disruption caused by the defendants at events. He contends that there is no real change of circumstances."

The judge said Mr McNally had argued that the consequence of protesters being excluded from Hans Crescent might be "drastic" and would discourage people from attending protests.