The US government is relinquishing its control of the internet's address system in a shift that could raise questions about the future direction of online innovation and communications.

The decision begins a long-planned transition affecting the stewardship of the Internet Corporation for Assigned Names and Numbers, or ICANN.

The not-for-profit agency was launched in 1998 by the US Commerce Department to govern the system that assigns website addresses and directs internet traffic.

The department's National Telecommunications and Information Administration (NTIA) hopes to end its oversight of ICANN's Internet Assigned Numbers Authority by the time its contract expires in September next year. The authority administers the technology that keeps computers connected to the web and steers internet traffic.

Proposals for a new ICANN stewardship will be accepted beginning next week at a conference in Singapore.

Although it is too early to tell how future oversight will be handled, the US government appears determined to hand over the reins to an entity without political entanglements.

"We will not accept a proposal that replaces the NTAI's role with a government-led or intergovernmental solution," Lawrence Strickling, assistant secretary at the Commerce Department, told reporters.

That statement might ease concerns that oversight of ICANN will be turned over to International Telecommunications Union, which is part of the United Nations.

Although other countries have had a say in how the internet works, the US government retained veto power over ICANN. That role has fuelled recurring debates about whether the US government exerts too much influence over technology that plays such a pivotal role in society and the economy.

The concerns about the United States' role in ICANN have intensified during the past nine months amid a series of media leaks from former NSA contractor Edward Snowden. The disclosures have revealed that government spy programmes have been collecting emails and other personal data from internet services for at least the past six years as part of the country's anti-terrorism efforts.

Mr Strickling said the "timing is right" for the Commerce Department to start to hand over ICANN.

Some internet groups say the US government should remain in a supervisory position to prevent leaders in other countries with a history of suppressing free speech from trying to manipulate ICANN in a way that censors online communications.