Peru's Machu Picchu, Jordan's Petra and the Acropolis were among the top contenders to be picked as the new seven Wonders of the World with just a few hours to go in a massive poll to pick the winners.

Voting in what may be the biggest ever global online poll closes at midnight ahead of the announcement of the winners at a ceremony tomorrow in Lisbon. More than 90 million people have voted so far.

Organisers say the contest is a unique exercise in levelling the global cultural playing field by putting hallmarks of European civilisation on an equal footing with other cultures such as Mexico's Mayas.

'We live in a Eurocentric world,' said Tia Vering, spokeswoman for the New 7 Wonders of the World (new7wonders.com) organisation.

'When have we ever compared symbols of European civilisation with, for instance, Mayan civilisation?'

Europe's leading contenders are the Acropolis in Athens, Rome's Colisseum and the Eiffel Tower. They are competing with Machu Picchu, Mexico's Chichen Itza ruins, India's Taj Mahal, Petra in Jordan, Christ Redeemer in Brazil and the statues of Easter Island.

The list prompted irritation in Italy, where leading Roman Catholic newspaper Avvenire criticised the lack of Christian sites among the contenders.

 'How is it possible that 2,000 years of great Christian civilisation -- for many centuries the civilisation full stop -- have not managed to produce a single 'wonder'?' Avvenire said in an editorial.

In all, 21 sites are contending. They also include the Statue of Liberty and Britain's Stonehenge, which is the oldest candidate, as well as the Sydney Opera House -- the newest.

Organisers will announce the list of the new seven wonders on Saturday but will not divulge the votes each received to avoid having 'first and second class wonders,' Vering said.

The ancient world's seven wonders were all located in the Mediterranean region and only one remains standing today -- the Pyramids of Giza. The originals were selected by one man, believed by many to be ancient Greek writer Antipater of Sidon.

Osama Abbas, Jordan's tourism minister, said the contest would change all that.

'The old wonders were chosen by one person, this was 2,500 years ago and most of them vanished, so it's about time that there are new wonders that the whole world can work for,' he said. 'I think it is fair and democratic, the whole world is voting and all continents are represented.'

Some countries have gone to lengths to promote their candidates, such as bus tickets in Brazil reminding travellers to vote and an Indian singer dedicating a song to the Taj Mahal.

But not everybody is enthused, arguing leading world sites cannot be chosen in a popular vote.

The UN Educational, Scientific and Cultural Organisation (Unesco) has refused to support the New 7 Wonders campaign, saying the media campaign should not be compared with its World Heritage List based on scientific work.

'This initiative cannot, in any significant and sustainable manner, contribute to the preservation of sites elected by this public,' it said in a statement, pointing out that the vote only includes people with access to the Internet.

As host of the only remaining ancient wonder, Egypt has removed the Pyramids of Giza from the competition and has asked UNESCO to assign 300 antiquities experts and intellectuals to choose new wonders.

The New 7 Wonders organisation, established by Swiss-Canadian adventurer Bernard Weber, will use half its revenues to fund restoration efforts worldwide, including re-creating the Bamiyan Buddha statue in Afghanistan. Reuters