Travolta and Johansson are promoting their new film in Venice

They are demonstrating against US movie blockbusters and the amount of money flying around Hollywood.

Dozens of protesters lined the red carpet for the premiere of Tom Hanks' movie The Terminal on Wednesday.

"This should be an event open equally to everyone, not an ostentatious show of wealth and Hollywood power," said 'no-global' organiser Luca Casarini.

The anti-capitalists parked a car decked out like a pirate ship outside the cinema where The Terminal was receiving its star-studded gala opening.

Mr Casarini said: "There are going to be more disturbances, we want our voice heard."

The protesters object to the change in direction taken by the Venice Film Festival, which this year is attracting a Hollywood A-list crowd to rival that of the Cannes Film Festival in France.

Jeering audience

A bomb threat on Thursday saw officials briefly shut down a dock where taxi boats were dropping off guests, but it was soon revealed to be a hoax.

The festival sees 21 films competing for the Golden Lion grand prize, which was won last year by Russian film The Return.

This year's entrants include a mix of art house movies and blockbusters such as the remake of Vanity Fair, starring Reese Witherspoon, and Nicole Kidman's Birth.

The hopes of Greece's Nikos Panayotopoulos got off to bad start when his film Delivery, about a pizza delivery boy in Athens, was jeered by the audience.

The winner of the Golden Lion will be chosen by a jury headed by British director John Boorman and aided by actress Scarlett Johansson and director Spike Lee.