A day before, an entourage of family and friends held a private viewing of her casket at the Whigham Funeral Home.

The convoy of back limousines and SUV's rolled in to the cordoned-off building as police braced for thousands of fans to pay their respects at what is fast shaping up to become one of the most-widely watched celebrity funerals ever.

The church, where invitees only will be admitted to the noon (1700 GMT) service, is Houston's childhood church and the place where her voice was first heard in public when she sang as a child in the church choir.

While the family of the soul diva had originally announced the funeral as a private service, they have now allowed TV cameras to offer live coverage, which will showcase some legendary names paying tribute to the chart-topping singer.

Huge screens have been erected outside for fans to view the proceedings. Hundreds of fans were already standing vigil outside both the church and funeral home, singing Houston's songs and holding placards and photos of the late singer, who died last weekend at age 48 in a Beverly Hills hotel room.

Soul greats Stevie Wonder and Aretha Franklin, her godmother, will sing, while Kevin Costner, her normally reclusive co-star in the hit film The Bodyguard, will address the mourners, People.com reported. Other stars expected to attend include Beyonce, Elton John, Oprah Winfrey, Chaka Khan, record producer Antonio LA Reid, Houston's cousin Dione Warwick, and music mogul Clive Davis who mentored the star.

Houston's death in a bathtub at the Beverly Hills Hilton last Saturday cast a dark shadow over the Grammy Awards the next day. The coroner is awaiting results of a toxicology report before announcing the cause of death. Once known as America's golden girl during the peak of her success for a decade from 1985, Houston later battled addictions to alcohol and drugs but claimed to have conquered her demons in 2009.

Houston's body was flown by private jet from Los Angeles to Newark, where the Whigham Funeral Home has become a shrine to the pop icon.

Flags on state government buildings will fly at half mast in her honour on Saturday, a decision that has provoked controversy because of her alleged years as a drug abuser.

New Jersey Governor Chris Christie defended the decision, calling Houston "a daughter of New Jersey," the New York Daily News reported.

"I am disturbed by people who believe that because her ultimate demise -and we don't know what is the cause of her death yet - but because of her history of substance abuse that somehow she's forfeited the good things that she did in her life," Christie said. "I just reject that on a human level."Author: Andy Goldberg