The U.S. government is taking a key step in relinquishing control of the internet's addressing system, fulfilling a promise made in the 1990s.

The Commerce Department's National Telecommunications and Information Administration said Thursday that it endorses a March proposal to turn full control over to a private international organization. All that remains is completing some contracts and operational testing. That's expected to be done in the coming months.

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The organization deals with matters including the assignment of internet suffixes such as ".com" and ".org" and the operation of the internet's "root servers," the master directories for telling web browsers where to find websites. Without them, users would have to remember a set of four numbers rather than "ap.org" to reach The Associated Press' website, for instance.

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This system has already been managed by a private organization, the Internet Corporation for Assigned Names and Numbers. But the U.S. government, which funded much of the internet's early development, has retained veto power.

Although the U.S. role has been minimal over the years, many foreign governments have complained that the internet can never be truly international if the U.S. retains veto power. They have sought instead to shift responsibility to an inter-governmental body such as the U.N. International Telecommunication Union.

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But business, academic and civil-society leaders balked, worried that U.N. involvement would threaten the openness that has allowed the internet to flourish. Concerns were also raised that U.N. control would give authoritarian states like China and Iran equal votes among other countries in influencing policies that affect free speech.

Lawrence E. Strickling, assistant secretary for communications and information at the Commerce Department, said the endorsed plan won't replace Commerce's role with a government-led or inter-governmental solution. Rather, ICANN will take full control after creating additional mechanisms to resolve disputes. ICANN has participants from business, academic and other communities in addition to governments.