ITU secretary-general Dr Hamadoun Toure has said any changes must be agreed on by all countries
The UN should not be allowed to take over control of the internet, Euro MPs have warned.
International governments are set to agree a new information and communications treaty next month.
Reports in the Russian press have suggested the Kremlin and others wanted control of key internet systems passed to a UN agency.
Internet control currently lies largely with US-based groups such as Icann, which regulates the web address system.
The European Parliament has said the UN's International Telecommunications Union (ITU) was "not the appropriate body" to have authority.
The ITU has said a new treaty was needed to ensure "the free flow of information around the world, promoting affordable and equitable access for all and laying the foundation for ongoing innovation and market growth".
The UN agency is hosting the conference to draw up the treaty between 3 and 14 December in Dubai.
Members of the European Parliament backed a resolution which urged member states to reject changes to the International Telecommunication Regulations (ITR) which would "negatively impact the internet, its architecture, operations, content and security, business relations, internet governance and the free flow of information online".
The ITRs are designed to ensure interoperability of telecoms equipment and services across the world. The last major revision was in 1988.
The negotiation process surrounding a new treaty has been criticised for being conducted largely out of the public's eye.
However, a site called Wcitleaks, run by researchers at George Mason University, has published several documents relating to the new treaty.
Among them was a proposal from Russia suggesting that the US should have less control over the internet's operation.
"Member states shall have equal rights to manage the internet, including in regard to the allotment, assignment and reclamation of internet numbering, naming, addressing and identification resources and to support for the operation and development of basic internet infrastructure," it said in a document submitted on 17 November.
The European Parliament's objection follows loud opposition from search giant Google, which has invited concerned internet users to sign a petition.
"The International Telecommunication Union is bringing together regulators from around the world to renegotiate a decades-old communications treaty," the company wrote.
"Some proposals could permit governments to censor legitimate speech - or even allow them to cut off internet access.
"Other proposals would require services like YouTube, Facebook, and Skype to pay new tolls in order to reach people across borders. This could limit access to information - particularly in emerging markets."
ITU secretary-general Dr Hamadoun Toure has signalled that if there were any serious disagreements he would try to avoid putting an issue to a majority vote.
"We never vote because voting means winners and losers and you can't afford that," he told the BBC in July.
"Whatever one single country does not accept will not pass."