By Sara Rossi and Gabriele Pileri

VENICE (Reuters) -Amazon founder Jeff Bezos and journalist Lauren Sanchez began three days of lavish wedding celebrations in Venice on Thursday with tight security shielding their VIP guests from protesters.

Bill Gates, Orlando Bloom and the Queen of Jordan were among the latest arrivals, joining Oprah Winfrey, Kris Jenner and Kim and Khloe Kardashian.

U.S. President Donald Trump's daughter Ivanka and son-in-law Jared Kushner, who showed up on Tuesday, have used the extra time for sightseeing and shopping.

Some 200-250 A-listers from show business, politics and finance are expected to take part in what has been widely dubbed "wedding of the century", estimated to cost around $50 million.

The event has stirred a debate about its impact on one of the world's most beautiful cities, with protesters seeing it as an example of Venice being gift-wrapped for ultra-rich outsiders, but others enjoying the spectacle and the spending.

An activist climbed one of the poles in the main St Mark's Square on Thursday, unfurling a banner with the words "The 1% ruins the world" to protest against the presence of the billionaire Bezos in Venice.

Guests were gathering on Thursday evening in the cloisters of Madonna dell'Orto, a medieval church in the central district of Cannaregio that hosts masterpieces by 16th century painter Tintoretto.

The city council banned pedestrians and water traffic from the area from 4.30 p.m. (1430 GMT) until midnight, to provide security and seclusion for the partygoers.

LUXURY CANALSIDE HOTEL

Bezos, 61, and Sanchez, 55, landed in Venice via helicopter on Wednesday and took up residence in the luxury Aman hotel, where rooms with a view of the Grand Canal go for at least 4,000 euros ($4,686) per night.

They are set to exchange vows on Friday on the small island of San Giorgio, opposite St Mark's Square, in a ceremony which, according to a senior City Hall official, will have no legal status under Italian law.

Some have speculated that the couple have already legally wed in the United States, sparing them from the bureaucracy associated with an Italian marriage.

Celebrations will conclude on Saturday with the main wedding bash to be held at one of the halls of the Arsenale, a vast former medieval shipyard turned into an art space in the eastern Castello district.

The "No Space for Bezos" movement is planning further demonstrations against an event they see as a sell-off of Venice, but by no means are all the locals hostile.

MONEY-SPINNER

Politicians, hoteliers and other residents say high-end events, rather than multitudes of low-spending daytrippers, are a better way to support the local economy, and dismiss the protesters as a fringe minority.

"If you look at what concretely the Bezos wedding brings for the good of Venice, there are only advantages and no disadvantages," Mattia Brandi, a local tour leader, told Reuters.

"If anything is different, it is because of the protesters ... They don't realise that it is them who are disrupting the quiet life of the city," he added.

Venice has hosted scores of VIP weddings. U.S. actor George Clooney and human rights lawyer Amal Alamuddin tied the knot there in 2014, and Indian billionaires Vinita Agarwal and Muqit Teja did so in 2011, without significant disruptions.

Bezos, executive chair of e-commerce giant Amazon and No. 4 on Forbes' billionaires list, got engaged to Sanchez in 2023, four years after the collapse of his 25-year marriage to MacKenzie Scott.

($1 = 0.8535 euros)

(Writing by Alvise Armellini and Keith Weir; Editing by Gavin Jones and Mark Heinrich)