Jared Kohler/CNET

The White House warned China today to end a campaign of cyberespionage against U.S. companies, saying in its toughest language yet on the issue that the hacking activity threatens to derail efforts to build stronger ties between the two countries.

U.S. companies are increasingly complaining that intellectual property is being stolen through attacks "emanating from China on an unprecedented scale," Tom Donilon, the president's national security adviser, said during a speech at the Asia Society in New York.

"The international community cannot afford to tolerate such activity from any country," Donilon said. "As the president said in the State of the Union, we will take action to protect our economy against cyberthreats."

Donilon's remarks come after a recent report that an "overwhelming percentage" of cyberattacks on U.S. corporations, government agencies, and organizations originate from an office building on the outskirts of Shanghai that's connected to the People's Liberation Army. China has denied any involvement and condemned the report for lack of hard evidence.

After The New York Times and The Wall Street Journal accused hackers in China of perpetrating months-long network breaches at the newspapers, a handful of companies have revealed that they too have been victims of recent hackings, including Apple, Facebook, Microsoft, and Twitter, although some of those are suspected of originating from Eastern Europe.

Saying that cybersecurity has become "a growing challenge" to the two countries' economic relationship, Donilon outlined the actions it would like the Chinese government to take to address U.S. cybersecurity concerns.

"We need a recognition of the urgency and scope of this problem and the risk it poses -- to international trade, to the reputation of Chinese industry, and to our overall relations," Donilon said. "Beijing should take serious steps to investigate and put a stop to these activities. Finally, we need China to engage with us in a constructive direct dialogue to establish acceptable norms of behavior in cyberspace."

The Obama administration has expanded its emphasis on cybersecurity in recent months, resulting in the signing of a long-anticipated executive order last month that allows companies to share confidential information with intelligence agencies without oversight. President Obama said at the time that the order would "strengthen our cyberdefenses by increasing information sharing and developing standards to protect our national security, our jobs, and our privacy."