Nicole  Kidman  hosted a party for some of her closest Australian celebrity friends - but there was no sign of her troubled husband Keith Urban.

The intimate cocktail party in Los Angeles on Friday night hosted by the Oscar winner was organised to celebrate the Academy Award nomination of director George Miller's animated comedy Happy Feet.

Country singing star Urban was expected to attend the party with his wife and the organisers yesterday could not explain his absence.

The couple are yet to appear at a public event together since Urban was released from a 90-day stint in rehab in January.

Urban last night appeared on US television in a pre-taped episode of Saturday Night Live and is scheduled to attend the Grammy Awards in Los Angeles tonight, where he has been nominated for best male country vocal performance for his single Once In A Lifetime.

Kidman appeared relaxed and happy at the party and mingled with the 60 guests.

The porcelain-skinned beauty spent several minutes chatting with Melbourne brothers Shane and Clay Jacobsen: the star and director of hit indy film Kenny.

The event, organised by LA-based cinema group Australians In Film, was held at the plush home of Australian Consul General Innes Willox in the up-market neighbourhood of Brentwood.

Guests included Rachel Griffiths and husband Andy Taylor, Melissa George and husband Claudio Dabed, Jacqueline McKenzie, Alan Dale, Simon Baker and wife Rebecca Rigg, Apocalypto cinematographer Dean Semler and actresses Kate Beahan and Kimberly Joseph.

Also present were Oscar nominees and Sydney film-makers Stuart Parkyn and Peter Templeman, who are up for best short film at the Academy Awards on February 25.

Actress Emilie de Ravin's attendance caused a stir: the Lost star was accompanied by her formerly estranged husband, American actor Josh Janowicz.

The couple, who are both 25, are understood to be back together after announcing their separation in January. They married only six months ago, after a five-year courtship.

De Ravin's spokesman refused to confirm whether the two, who were married in the Melbourne beachside suburb of Mount Eliza in a private ceremony in June, were giving their marriage a second chance.

One high-profile Aussie star missing from the gathering of the Tinseltown's "gum leaf mafia" was Heath Ledger, who was hosting his own party across town.

The event, held at Ledger and his partner Michelle Williams' Hollywood Hills mansion, was initially suspected by guests to be a surprise celebration of their rumoured secret marriage but the event turned out to be a birthday party for a close friend of the Brokeback Mountain star.

Among the 150 guests partying into the wee hours at Ledger's bash were former Ally McBeal star Portia de Rossi and young AFI award winner Emily Barclay, who is in the process of playing Williams' sister in a new film about the legendary British sibling writers the Brontes.

Meanwhile across the Atlantic, Australian actress Cate Blanchett was walking the red carpet in Berlin for the European premiere of The Good German.

Source: news.com.au