NAIROBI (Reuters) - Campaigners for a loosely regulated Internet are alarmed at the risk to Web freedom from fast-growing BRIC and other emerging economies seeking more say in how the online realm is policed.

They fear tighter government control by authoritarian countries will strangle the liberal culture which has allowed the still-young Internet to thrive as an engine of economic growth and innovation.

China, Russia, Tajikistan and Uzbekistan last month proposed to the United Nations a global code of conduct embodying among others the principle that "policy authority for Internet-related public issues is the sovereign right of states."

China exercises comprehensive censorship and surveillance over its Internet population of half a billion, the world's biggest, while Uzbekistan is considered an "enemy of the Internet" by press-freedom group Reporters without Borders.

"Some of those countries have a more authoritarian character, and so they're accustomed to interfering with what would otherwise be thought to be freedom of expression," Internet pioneer Vint Cerf told Reuters in an interview at last week's Internet Governance Forum in Nairobi.

India, Brazil and South Africa have also proposed setting up a new UN body to form global Internet policies -- frustrated that their growing economic power is not reflected in the multiple bodies that together keep the Internet running.

The BRICs are not alone in favoring more control.

French President Nicolas Sarkozy, who has championed a law to deal with online copyright piracy by cutting offenders off the Internet, this year convened an Internet summit in Paris, the e-g8, where he made the case for more regulation.

The issues at stake are complex. The same relative absence of regulation that has spurred enormous innovation and empowered the revolutionaries of the Arab Spring has also allowed the spread of child pornography and global online fraud.

The Internet now accounts for 21 percent of GDP growth in mature economies, according to a recent McKinsey study, while its power to mobilize political opposition through sites like Twitter has alarmed governments from China to Iran to Egypt.

Many governments are no longer content to share power in this crucial arena with companies, non-profit organizations, engineers and ordinary citizens through organizations they see as ineffectual.

Currently, the Internet is run by a loose consensus of overlapping interest groups and institutions that have grown up as it has evolved from an academic network under the control of the U.S. government to a global, commercial powerhouse.

Some of these come together once a year at the Internet Governance Forum, which was set up by the United Nations in 2005 in response to a general bewilderment that no one was in charge of something so big and important.

But the IGF's lack of decision-making powers are increasingly frustrating many governments, whose attempts to stop cybercrime, copyright piracy or block content they consider undesirable are largely futile on the borderless Internet.

"We are trying to go into a discussion that makes the participation -- and also the government participation -- of developing countries more effective," Romulo Neves of Brazil's Ministry of External Relations told Reuters in Nairobi.

Neves was emphatic that the India-Brazil-South Africa (IBSA) proposal was a draft and a compromise between three countries, and that Brazil supported the so-called multi-stakeholder model embodied by the IGF.

But many delegates were not convinced, said Lesley Cowley, chief executive of British Internet registry Nominet which manages .uk domains.

"The IBSA proposal for a new UN body that would provide oversight of the existing bodies in this field met with strong criticism from many of those present, who believe this would be an inter-governmental mechanism," she told Reuters.

Cowley said she saw a "long and difficult debate" ahead -- a feeling echoed by Cerf, who said some means would need to be found to deal at least with issues like child porn and fraud.

"If you don't have reciprocity, I don't know how on earth you ever get to the point where you can deal with some of the abuses on the Net," he said.

"So I think there's a big debate that needs to happen, and the IGF may be the best place to start. It won't end there, but it is a place to start."

(Editing by Chris Wickham and David Cowell)

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