The presidents of China and Pakistan pledged closer cooperation on security and economic issues today, as the two sides signed several bilateral agreements, according to dpa. State television quoted Chinese President Hu Jintao as saying the fight against the "three forces" of terrorism, religious extremism and separatism was "in the interests of both peoples" and would promote regional security. Pakistani President Asif Ali Zardari told Hu that Islamabad was willing to combat the "three forces" with China, and wanted to deepen trade and economic cooperation with its neighbour, China Central Television reported. Zardari welcomed more Chinese firms to invest in Pakistan, the broadcaster said. The presidents witnessed the signing of several agreements covering economic cooperation, agriculture, culture, justice, news and hygiene, it said. But the report did not mention any discussion or agreements on expanding China's nuclear energy cooperation with Pakistan. The China Daily newspaper on Monday quoted Masood Khan, Pakistan's ambassador to China, as saying no new deals on nuclear energy were expected to be signed during Zardari's visit to China. China has reportedly agreed to build two new reactors at Pakistan's Chashma nuclear power complex, prompting US officials to ask if China needs to seek an exemption from international regulations on export of nuclear technology, as Washington did it when it signed a nuclear power deal with India in 2008. Zardari is scheduled to meet Chinese Premier Wen Jiabao on Thursday and travel to Shanghai to attend the World Expo 2010. -- SPA