RIO DE JANEIRO - ACTORS posing as Portugal's royal family joined the fictional King Momo at the start of Rio de Janeiro's Carnival celebrations on Tuesday to mark 200 years since the court's arrival in Brazil.

Various samba groups have chosen as their parade theme the 1808 event that briefly made Rio the capital of the Portuguese empire. The royals had fled from Napoleon's advancing armies.

Carnival King Momo in red and golden robes and his samba-dancing entourage crossed the city in three antique carriages escorted by 19th-century guards on horseback.

Mayor Cesar Maia called Rio's Carnival 'Earth's biggest party' and said the festival was growing bigger and more spontaneous every year.

'Never before have I received so many e-mails complaining of the number of street parties ... . It means there are more and more people in the streets, more spectators, more people having a good time, enjoying the soul of Rio,' MAYOR Maia said during the ceremony.

An estimated 705,000 tourists will visit Rio in the coming days, up about 2 per cent from last year, authorities said.

King Momo, played by architect Alex de Oliveira, called on his revelling subjects to have fun and use condoms - 'the best Carnival costume.' The government is giving away 19 million condoms before and during the raucous party.

Weeks before the official start of Carnival, loud neighbourhood processions, known as 'blocos' have jammed streets on weekends.

The highlight of the Carnival celebrations are two parades on Sunday and Monday night by 12 samba groups, each featuring up to 6,000 dancers in the Sambadrome stadium. Monday and Tuesday of next week are public holidays.

The most popular parades are in Rio de Janeiro, and in the northeastern cities of Salvador and Recife. -- REUTERS