WASHINGTON — The Federal Communications Commission on Wednesday halted new government rules related to data security from taking effect this week, in a potential prelude to a broader repeal of privacy protections for users of high-speed internet.

After a 2-to-1, party-line vote by the Republican-led commission, Ajit Pai, the chairman, announced that a portion of privacy rules passed in October would be temporarily stayed.

The rules, which were to take effect on Thursday, required high-speed internet providers like AT&T and Comcast to secure their customers’ data against hacking and other unauthorized uses.

Mr. Pai, in a sign that additional swipes at privacy rules may be in store, also said the commission should not be engaged in any policing of broadband providers over online privacy. He said the Federal Trade Commission should instead oversee the broadband and web industries.