U.S. Secretary of State Hillary Clinton is urging software and other high-tech firms not to sell technology that would help repressive governments restrict Internet freedoms.

Secretary Clinton made her remarks Thursday in The Hague at an international conference on Internet freedom.

Clinton told her audience that when ideas are blocked, information deleted, conversations stifled, and people constrained in their choices, the Internet is diminished for everyone.

She said it was an “urgent task” to preserve full liberties online and that corporations can protect their own reputations by thinking twice before doing business with repressive governments.

The top U.S. diplomat urged companies to be vigilant about selling their products to countries that will use them to help governments abuse their citizens' digital rights. She said that when companies sell surveillance equipment to the Syrian or Iranian security agency, or in past times to Libya, “there can be no doubt it will be used to violate rights.”

Dutch Foreign Minister Uri Rosenthal said it is “vital” that technology developed in democratic countries not become “complicit” in human rights abuses.

Clinton also said some governments use Internet governance issues as a cover to push an agenda that would justify restricting human rights online. She did not name any countries as having such an agenda, but aides she was referring to, among other things, a proposed “code of conduct” for information security introduced at a United Nations General Assembly earlier this year by Russia, China, Tajikistan and Uzbekistan.

Social media sites like Facebook, YouTube and Twitter have driven revolutions around the globe. They have linked like-minded and disparate groups in several Middle Eastern countries in the social and political uprisings known as the Arab Spring.