The Economy & The Fiscal Cliff
• U.S. stocks increase in first day of 2013 trading following "cliff" deal
• With "cliff" deal reached, House members turn attention to Sandy bill
• Despite deal reached, budget fights anticipated over next coming months
• LIVE COVERAGE: Latest political news from Reuters
BEIJING/WASHINGTON - China said on Monday it opposed all forms of cyberattacks but there was no proof that North Korea was responsible for the hacking of Sony Pictures, as the United States has said.