China expresses regret over expanded South Korean air zone December 10, 2013 -- Updated 0440 GMT (1240 HKT) A man looks at Chinese aircraft on display during a visit to a museum in Beijing on November 29. China has voiced "regret" over South Korea's decision to expand its air defense zone. The expanded zone includes an area claimed by both countries. China newly declared air defense zone has raised tensions in the region Hong Kong (CNN) -- China has expressed "regret" over South Korea's decision to expand its air defense zone to include an area claimed by both countries, the country's official Xinhua news agency has reported. South Korea's move came after China declared an Air Defense Identification Zone (ADIZ) in the East China Sea last month. The Chinese zone covers a disputed reef, called the Suyan rock by China and Ieodo by South Korea. China's foreign ministry spokesman Hong Lei said on Monday that the two countries had maintained communication over the zones. The Air Defense Identification Zone is not territorial airspace. It is established by a country in public airspace outside its territorial airspace for identification and early-warning. It has nothing to do with maritime and air jurisdiction," he said. READ: South Korea expands air defense zone The expanded South Korean zone will go into effect on December 15. South Korea Defense Ministry spokesman Kim Min-seok said the move was in accordance with international norms. The new KADIZ's southern region was adjusted so that it is in line with Incheon Flight Information Region, which is internationally used (recognized) and does not overlap with that of neighboring countries. The adjusted region includes airspace over Ieodo waters and Marado and Hongdo islands which is our territory. China newly declared air defense zone has raised tensions in the region, with the United States, Japan and South Korea lodging objections to the zone. Asia's disputed islands South Korea has expanded its air defense zone to include an area claimed by Beijing and Seoul. December 1, 2013 -- Updated 0103 GMT (0903 HKT) Three major U.S. airlines comply with China's demands to be notified of plans to traverse the air defense zone over the East China Sea. President Xi Jinping has reshaped China's foreign policy by recalibrating its stresses on sovereignty and stability, writes Shen Dingli. Two U.S. military aircraft flew into China's new air defense zone, an action that could inflame power tensions, a U.S. official said. Tensions magnified among the world's top three economies over China's controversial new air defense zone. November 27, 2013 -- Updated 0024 GMT (0824 HKT) CNN's David McKenzie reports from Beijing on why the Chinese claim sovereignty over an area in the East China Sea. November 1, 2013 -- Updated 0042 GMT (0842 HKT) Surprise, surprise, Japan and China are still not getting along, writes Jeff Kingston of Temple University in Japan. October 25, 2013 -- Updated 0935 GMT (1735 HKT) Japan is using YouTube to bolster assertions of ownership over islands also claimed by neighboring China and South Korea. August 6, 2013 -- Updated 0100 GMT (0900 HKT) Players join the ranks of the country's military to take on the enemy in China's first online game co-developed by the People's Liberation Army. April 24, 2013 -- Updated 1016 GMT (1816 HKT) The fragile relationship between China and Japan came under fresh strain as ships from both sides crowded around the disputed islands. April 8, 2013 -- Updated 1753 GMT (0153 HKT) Sightseeing cruises soon to set sail to China's newest city, Sansha, located on a disputed island in the South China Sea, a Chinese official said. November 15, 2012 -- Updated 0854 GMT (1654 HKT) China uses perceived provocations as a chance to change the status-quo in its favor, writes Stephanie Kleine-Ahlbrandt.