Tantalising details have emerged of George Clooney's wedding dinner, with Hollywood stars reportedly to dine Saturday on lobster, wild mushrooms and figs at a banquet in Venice fit for the gods.

Clooney said goodbye to bachelorhood Friday night with a stag party at his favourite restaurant but was spotted at brunch looking hangover-free as he gears up for a day of celebrations with his glamorous lawyer bride-to-be.

The actor had swept into the floating city on Friday with his British fiancee Amal Alamuddin aboard a water taxi dubbed "Amore", zipping up the Grand Canal to cheers from fans at the start of nuptials set to span the weekend.

As evening approached and girls across the world sobbed, one of the world's most eligible bachelors set out in black tie for an all-boys do with friends to celebrate one of his last nights as a single man.

After shaking off paparazzi, Clooney and his chums headed to Da Ivo near Saint Mark's Square for the venue's prized Venetian and Tuscan delicacies.

A waiter at the restaurant said the group tucked into stuffed zucchini flowers and fresh tagliolini pasta with truffles.

The feasting was set to continue Saturday evening, with some 130 guests being whisked to the exclusive seven-star Aman resort within the 450-year-old Palazzo Papadopoli by gondola and speed boat, under police escort.

There they'll be met in the garden -- an oasis sheltered from the bustle of the canal -- with lashings of bubbly and canapes, including polenta with wild mushrooms and prosciutto ham with figs, according to a source.

They will then sit down in the main library to a sumptuous five-course dinner which will include lemon risotto with lobster, the source said.

Mysterious ceremony before dinner

Intriguing reports also emerged of a ceremony to be held at the hotel before dinner.

Clooney was spotted in the garden of the luxurious Cipriani hotel Saturday with friends Cindy Crawford and her husband Rande Gerber -- tipped to be Clooney's best man.

Dressed in a casual blue shirt, he looked relaxed and fresh despite having reportedly rounded off the night before with tequila shots and cigars.

The 53-year-old actor had 100 cases of his own tequila label flown in for his wedding and was expected to have cracked open bottles of the award-winning tipple at the stag party.

Clooney's Lebanon-born bride-to-be was snapped Friday evening in a red gown at her own soiree with close friends including Ellen Barkin -- who threw the 36-year-old human rights lawyer a hen party several weeks ago.

In a Cinderella moment, Alamuddin lost her shoe after the stiletto heel got caught in a gap in the slatted floor in front of the hotel, but she recovered in style.

Stars Brad Pitt, Angelina Jolie and musician Bono were tipped to be on their way to join Matt Damon and others for the party of the year.

'When I fall in love'

The Aman's restaurant will be turned into a nightclub where they'll dance the night away, with Lana Del Rey reportedly preparing to serenade the couple and Clooney dedicating the song "When I fall in Love" to Alamuddin.

A string orchestra and jazz trio are also expected to perform a number of songs, including the uber-romantic "Smoke Gets in Your Eyes", a ballad made famous by The Platters in 1958.

Rome's former mayor Walter Veltroni, a long-term friend of Clooney's, will be performing the civil ceremony, which is likely to be held on Monday in the town hall, the stunning Ca' Farsetti, a 14th-century palace opposite the Aman hotel.

Clooney, who has owned a home in northern Italy for years, was married once before, to "Mad Men" actress Talia Balsam, but the pair split in 1993, just before his breakout role in "ER" propelled him to the status of global sex symbol.

Alamuddin's rights work has involved representing Wikileaks founder Julian Assange.

She moved to Britain as a three-year-old.