Beijing, Aug 25 : China's Ministry of Water Resources on Friday activated a level-IV emergency response to flooding in 13 provincial-level regions. The regions are Jiangsu, Anhui, Shandong, Henan, Hubei, Hunan, Chongqing, Sichuan, Guizhou, Yunnan, Tibet, Shaanxi and Gansu, Xinhua news agency quoted the Ministry as saying From Friday to Sunday, heavy rain will sharply increase water levels in rivers including parts of the Yangtze and Huaihe river,s the Ministry said, adding that some small and medium-sized rivers in affected areas may see floods exceeding warning levels. It urged relevant water conservancy departments to closely monitor rain situations and strengthen early warning, with focus on ensuring the safety of reservoirs and the prevention of mountain torrents and floods in small and medium-sized rivers. /IANS