Kramer said the United States will have to remain open to proposals that would improve security or expand Internet access to areas that have little or no access.
But he emphasized that certain proposals are non-negotiable, including a plan pushed by European telecommunications companies that would allow them to charge more to carry international traffic.
The proposal by the European Telecommunications Network Operators' Association could force websites like Google, Facebook and Netflix to pay fees to network operators around the world.
Karmer warned that the proposal could stifle the freedom and openness of the Internet and that it is gaining support in some countries in Africa and the Middle East.
Ross LaJeunesse, global head of free expression and international relations for Google and a member of the U.S. delegation to the conference, said the proposal is a "real threat to the future of the net as we know it today."
He argued that the ITU is poor forum for discussing changes to the management of the Internet because only governments are allowed to negotiate changes to the treaties. He argued that the Internet has been successful because of innovations from the private sector.
LaJeunesse said the ITU is not transparent and that authoritarian regimes like Russia, Syria and Iran will use any new powers over the Internet to crack down on their citizens.
Robert McDowell, a Republican member of the Federal Communications Commission, urged the delegates to be wary of even "seemingly small or innocuous changes to the treaty."
He argued that the conference shouldn't become a battle between developed countries and developing countries.
"The developing world benefits more greatly, proportionally speaking, from an unfettered Internet than we do," McDowell said.