The Sugar Plum Fairy in English National Ballet’s production of The Nutcracker had to confront angry colleagues before yesterday’s matinee performance after she was revealed to be a member of the British National Party.

Simone Clarke, 36, was named by a newspaper that had infiltrated the party and obtained a membership list.

Others reported to be BNP members by The Guardian included Annabel Geddes, founder of the London Dungeon and a former director of the London Tourist Board, and Peter Bradbury, a leading proponent of complementary medicine who has links to the Prince of Wales.

Clarke said she believed that immigration had “really got out of hand”. She added: “If everyone who thinks like I do joined, it would really make a difference.”

Her opposition to immigration is a sensitive issue at the ballet company because nine of her ten fellow principal dancers — including the father of her child — are immigrants.

Yat-Sen Chang, who has been Clarke’s partner for five years, was born in Cuba and has a Chinese father.

Only one other principal, Sarah McIlroy, is British. The rest are Cuban, Estonian, Georgian, Russian, Czech or Japanese.

The dancers were instructed not to comment yesterday, but Clarke said in a recent interview that she does not mix with the other performers outside working hours. “I don’t socialise with people in the company,” she said. “It’s all too much.”

A spokeswoman for English National Ballet declined to comment on Clarke’s private views but said that the company did not share them. “We are an equal opportunities employer,” she said. “We pride ourselves on the diversity in the company.”

Members of the audience at yesterday’s performance said that Clarke’s views did affect their opinion of English National Ballet. Jasmine Sandhu, 23, who travelled from Leicester to see the show, was upset by the revelation before she went in. “I wish I had found out afterwards,” she said. “It will damage English National Ballet’s reputation.”

Maeve Bridgland, who was taking her granddaughter to the ballet, said that it would not affect her appreciation of the performance. “But I shall have a look now to see [whether the other performers treat her differently].”

Clarke has said previously that she is considering other careers, including property development. “I’ve even thought of becoming a plumber. I enjoy my job . . . but some things need to change. It’s a question of when to start.”

Ms Geddes, who left the London Tourist Board in 1984, was reported to believe that Asian immigrants are a “bloody bore” and that black people are “ghastly”. She told the undercover journalist: “I’m a racist. We’ve got to keep little UK basically Anglo-Saxon.”

She could not be reached for comment yesterday. Visit London, formerly the London Tourist Board, distanced itself from its former director yesterday and the London Dungeon said that it had had no connection with her since she sold the company in 1984. Mr Bradbury could not be reached for comment last night.

Other people said to be members or lapsed members of the party are said to include a servant of the Queen who lives at Buckingham Palace, a former Miss England and several former Conservative Party activists. The Palace said that its servants had the right to their personal preferences “as long as they are not actively campaigning”.

The list of names suggests that the party is actively pursuing middle-class voters in Central London to augment its traditional recruiting grounds in East London, West Yorkshire, parts of Lancashire and some Midlands cities. Nick Griffin, the party leader, told supporters last month that broad-based support was vital to electoral success.

Seats of power

46 council seats held by the BNP in England

229,000 votes for the BNP out of a total of seven million cast in the local elections in May

Times Recommends

• What makes the perfect mum?
• To keep me stress-free, no more awareness days, please
• What do lottery winners buy?