WASHINGTON — The United States and China are negotiating what could become the first arms control accord for cyberspace, embracing a commitment by each country that it will not be the first to use cyberweapons to cripple the other’s critical infrastructure during peacetime, according to officials involved in the talks.

While such an agreement could address attacks on power stations, banking systems, cellphone networks and hospitals, it would not, at least in its first version, protect against most of the attacks that China has been accused of conducting in the United States, including the widespread poaching of intellectual property and the theft of millions of government employees’ personal data.

The negotiations have been conducted with urgency in recent weeks, with a goal to announce an agreement when President Xi Jinping of China arrives in Washington for a state visit on Thursday. President Obama hinted at the negotiations on Wednesday, when he told the Business Roundtable that the rising number of cyberattacks would “probably be one of the biggest topics” of the summit meeting, and that his goal was to see “if we and the Chinese are able to coalesce around a process for negotiations” that would ultimately “bring a lot of other countries along.”

But a senior administration official involved in the discussions cautioned that an initial statement between Mr. Obama and Mr. Xi may not contain “a specific, detailed mention” of a prohibition on attacking critical infrastructure. Rather, it would be a more “generic embrace” of a code of conduct adopted recently by a working group at the United Nations.