China Slams 'Cyber Terrorism' as Obama Vows N. Korea Review

China condemned "cyber terrorism" on Monday after U.S. President Barack Obama pledged to consider officially labeling North Korea, accused by Washington of hacking Sony Pictures, a state sponsor of terrorism.

The Chinese foreign ministry statement came after talks Sunday between Foreign Minister Wang Yi and his counterpart John Kerry and followed calls by Washington for China and other nations for help in deterring future attacks.

Obama, while saying that the alleged hack was not an act of war, has promised an unspecified "proportionate" response.

South Korea's nuclear power plant operator, meanwhile, launched a two-day drill to test its ability to thwart a cyber attack, though the exercise did not appear to be directly linked to the U.S.-North Korea row.

In Beijing, a foreign ministry statement on Monday said the country "opposes cyber attacks and cyber terrorism in all of its forms," without referring directly to China's ally North Korea.

China "opposes any country or individual using facilities in other countries to launch cyber attacks toward a third country," it said.

Washington accuses Pyongyang of being behind the hack that led to the release of embarrassing company emails and caused Sony executives to halt the debut of the comedy action film "The Interview."

The film about a fictional CIA plot to kill the country's leader infuriated North Korea, although Pyongyang has repeatedly denied it was behind the cyber assault.

Despite calls from Republican critics for a robust response to the alleged hack, Obama told CNN in an interview: "I don't think it was an act of war. I think it was an act of cyber vandalism that was very costly, very expensive. We take it very seriously."

He also promised to "review" whether to return North Korea to the U.S. list of state sponsors of terrorism, but added: "We've got very clear criteria as to what it means for a state to sponsor terrorism. And we don't make those judgments just based on the news of the day."

The hermit state threatened to hit back at the White House and other U.S. targets if it was sanctioned over the alleged hacking.

The North's National Defense Commission, in a statement on the official news agency, said its army and people "are fully ready to stand in confrontation with the U.S. in all war spaces including cyber warfare space to blow up those citadels."

According to the FBI, there is "significant overlap" between the Sony Pictures attack and other "malicious cyber-activity" with direct links to Pyongyang, including an attack last year on South Korean banks blamed on the North.

The South's Korea Hydro and Nuclear Power Co (KHNP) on Monday began conducting drills at its four nuclear plant complexes after a series of online information leaks by a suspected hacker.

The hacker, using an account entitled "president of the anti-nuclear reactor group", published a variety of information on Twitter, including designs and manuals for two reactors as well as personal information on some 10,000 KHNP employees.

There did not appear to be any link between the drill and the Sony Pictures hack, and North Korea says it has never attempted or made a cyber attack on South Korea.