World leaders and tech giants have gathered for a historic summit in an effort to crack down on online hate in the wake of the Christchurch shooting.

New Zealand Prime Minister Jacinda Ardern organized the event, hosted in Paris by French President Emmanuel Macron, where she unveiled her initiative known as the “Christchurch Call.”

Seventeen countries and eight tech giants came together in support of Ardern’s initiative which commits foreign countries and tech giants to tackle the spread of dangerous content on social media.

Countries including Australia, Germany, Japan, the Netherlands, Spain, India and Sweden said they backed the initiative. The United States did not sign up to the pledge.

A statement from the White House said while the U.S. is “not currently in a position to join the endorsement” they continue to “support the overall goals reflected in the call.”

The statement, however, goes on to suggest concerns about the potential risks to free speech: “We continue to be proactive in our efforts to counter terrorist content online while also continuing to respect freedom of expression and freedom of the press.

“Further, we maintain that the best tool to defeat terrorist speech is productive speech, and thus we emphasize the importance of promoting credible, alternative narratives as the primary means by which we can defeat terrorist messaging,” the statement said.