Google has called on other internet companies to help it "hold the line" against governments and others who want to censor content on the web.

Nicole Wong, Google’s deputy general counsel, who has the final say on whether to block controversial videos on YouTube and on maintaining Google search links, said she had been forced to accede to demands to remove videos when the safety of Google employees was threatened.

Ms Wong, nicknamed "the decider", told a panel discussion at the South By Southwest Interactive conference in Austin, Texas, that companies had to present a united front against demands for censorship. Google and its subsidiary online properties had been blocked in 24 countries in the past seven years, she said.

She described how companies such as Google often had to deal with intimidating phone calls demanding that something be taken down. "They say, 'other guys down the street are doing it, you should too'.”

If internet companies united, then such pressure could be resisted. "We can hold the line. We can make sure there is a legal process. They can't pick us off," she said.

Google, Yahoo! and Microsoft have been criticised for co-operating with demands to block content or provide information about users, particularly in China. Reporters Without Borders said in a report earlier this month that US-based internet companies were not going far enough to protect their users from "oppressive" governments.

Ms Wong said that Google employees had been detained and governments had subjected the company to intimidation. In some instances, Google had decided to block content for specific countries on YouTube, which it owns, applying the site's rules of service against content promoting hate or violence.

YouTube had been blocked for nearly a year in Turkey, she told the meeting.

The row began when a Turkish judge ordered telecom providers to block access to the site because it was carrying videos that insulted Mustafa Kemal Ataturk, the founder of modern Turkey, which is a criminal offence in the country. Turkish prosecutors then objected to dozens of other videos allegedly attacking Ataturk or "Turkishnesss" or promoting Kurds. Ms Wong agreed to block videos that were illegal in Turkey so that they could not be viewed in Turkey. When, last June, a Turkish prosecutor demanded they be blocked worldwide, Google refused and the Government blocked access to the whole site.

"We are at the point when we are playing all of our legal and policy cards. This is no longer in my hands. There are only so many tools in the toolbox to deal with this kind of thing."

She called for an international agreement on how to handle content. It might be better for governments to decide what should or should not be censored "rather than have these issues bubble up through me" or other companies.

Ms Wong cited an example in India in 2007 when a row broke out over criticism of a religious political party in Mumbai on Google's Orkut social network. There were demands for Google to censor the Orkut communities responsible. Protesters took to the streets and rioting threatened to break out outside Google's offices in the city. Ms Wong decided to remove comments attacking a Hindu deity but left alone other political comments.

"As much as you want to defend free speech, when things get violent you have to make a decision and so my decisions tend to err towards protecting people on the ground," she said.

Admitting that such judgment calls were hard, she said she felt the right balance had been struck at the time. "Candidly, would we do it again? I don’t know," she added.

That is why she felt there needed to be "something more institutional than a single person".

'If you go company by company it starts to feel very arbitrary," she said, adding that the next big company might be coming out of China or Argentina. That was why international standards were needed on freedom of expression and free speech.

A good first step, she said, was the Global Network Initiative, set up last October with Yahoo!, Microsoft, human rights organisations and non-governmental bodies to try to frame a set of guidelines for organisations facing requests to remove content.

If governments were to take on the censorship role, as Australia has done by running trials to block child abuse content for the whole country, they would have to transparent about the way they made decisions, she added.

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