MORE than 50 Russian acrobats, trapeze artists and jugglers are heading home after the promoters of their circus were forced to cancel at the last minute. The show had been scheduled to begin tomorrow and run to July 31, but was cancelled because of delays in securing entry permits for performing animals. William Wong Hing, shows manager for promoter Capital Artists Limited, promised to reimburse $1.5 million in ticket sales. More than 50 Russian performers arrived last week without their animals to prepare for the shows. Yesterday they prepared to leave, spending the day sight-seeing or at their hotels. Mr Wong has threatened a $4 million lawsuit against the Urban Council for losses he says his company incurred due to the cancellation. Because of delays by the Urban Council in approving the circus, the Agriculture and Fisheries Department was not able to process the applications in time for the five bears, 23 dogs, one kangaroo, one puma, one python and one monkey to be allowed into the territory. ''It's just ridiculous. We are more than mad about this . . . and our lawyers are checking to see if we have a case,'' Mr Wong said. The council's 12-member entertainment select committee only decided on July 1 that Capital could hold its circus at the Hong Kong Coliseum, after a rival promoter threatened to sue the Urban Council if permission were granted. Worldwide Entertainment Limited claims the Urban Services Department (USD) has reneged on a 1990 agreement that it would be the only company to bring circuses until 1996. The USD says no such agreement was made. But the Urban Council rejected at least two applications by Capital before it approved the show. When the approval finally came on July 1, three of 12 members on the entertainment select committee voted for it. The other nine members abstained. But it was too late for the Agriculture and Fisheries Department to process the applications for the animals, as a 42-working-day wait is standard procedure. However, Mr Wong said, the department had privately assured him that approval would be granted faster, although it was kept as an informal understanding because others with similar applications would have claimed special treatment was being given. Yesterday, after the South China Morning Post reported the problems the promoters had faced, Mr Wong said the Agriculture and Fisheries Department notified him that approval could not be granted for several more weeks, and the show was cancelled. Mr Wong said more than $1 million had been spent on television, newspaper and billboard adverts; $800,000 was spent as a deposit for the Coliseum; and between $1 million and $2 million went on sets and preparations for the animals, to fly the Russian performers to Hong Kong, to house them at the Regal Riverside Hotel in Sha Tin, as well as allowances and contractual obligations. Chairman of the Urban Council, Ronald Leung Ding-bong, said the council would fight any legal action.