Officials from more than 60 countries have been meeting in France to discuss ways of combating racism on the internet.
Participants aim to combat xenophobic propaganda on the net
Divisions have emerged between France and the United States over how to tackle the problem.
France wants tougher regulations, and believes there is a direct link between racist propaganda on the web and a surge in hate crimes in recent years.
But the US says it is against any restrictions on freedom of speech.
"We are at a particular 'hinge' moment in our common fight against intolerance," French Foreign Minister Michel Barnier told the conference in Paris.
"Our responsibility is to underline that by its own characteristics - notably, immediacy and anonymity - the internet has seduced the networks of intolerance."
He said France had noted a "clear relationship" between racist, anti-Semitic and xenophobic propaganda and hate crimes.
The two-day meeting is being hosted by the Organisation for Security and Co-operation in Europe.
Service providers' help
US Assistant Attorney General Dan Bryant said the US believed the best way to tackle the problem was through promoting tolerance and understanding.
"We believe that government efforts to regulate bias-motivated speech on the internet are fundamentally mistaken," he said.
"At the same time, however, the United States has not stood and will not stand idly by, when individuals cross the line from protected speech to criminal conduct."
The conference was told that part of the problem is that websites with European content are often housed in the US.
The Wiesenthal Center, which has been tracking race-hate sites for several years, said internet service providers could help in the fight.
"If you focus the discussion exclusively on speech, we will never close the divide and only terrorists and hate groups will win," said Rabbi Abraham Cooper, associate dean of the Los Angeles-based centre.
"We need to get the attention of the online community," he told Reuters news agency at the conference.
"They have a lot more clout to address the vast majority of this problem than any of the diplomats sitting in this room."