The critics argue that the wildfire growth of online services has been driven by the ability to deliver services to anyone.

If telecoms firms could block or slow down access to their customers unless services providers paid extra, that would be threatened, they say.

After a three-day hearing, the committee rejected an amendment from Republican senator Olympia Snowe and Democrat Byron Dorgan which aimed to prohibit phone and cable companies from limiting access to their high-speed internet networks based on site content or financial arrangements.

"What's at stake is the internet in the 21st century," said Ms Snowe. "This is the preservation of digital democracy."

Limited access?

Hundreds of interest groups - including Google, eBay and Amazon - have been lobbying for protection from any moves by broadband providers to limit the access of customers.

The proposals aims to make it easier for telecoms firms to offer video services around America by replacing 30,000 local franchise boards with a national system overseen by the Federal Communications Commission (FCC).

Supporters claim it will save consumers money, while critics fear it will see net providers decide which websites and services customers can visit and use.

The bill has already won backing in Congress, but Senator John Kerry, who supports the Snowe amendment, has threatened to delay it with a filibuster - a method used to delay or postpone the passage of legislation.