TOKYO : Taking advantage of the coronavirus pandemic, China has further staked its territorial claims in the East China Sea, Japan said in its annual defence review.The report said that China "is continuing to attempt to alter the status quo in the East China Sea and the South China Sea".Citing the defence white paper, Nikkei Asian Review reported that there have been "relentless" intrusions in the areas around the Senkaku islands as called by Japan or Diaoyu in China.Besides, China has been asserting its claims in the recent days in the South China Sea by establishing administrative districts around disputed islands while the neighbouring countries have been busy with dealing with the COVID-19 crisis.The recent Chinese intrusions have not.