India and China on Monday discussed the vexed border issue as Indian Army chief General Dalbir Singh met top officials of the Chinese Army including the PLA commander.Gen Singh, who is on a four-day China visit, will go to the eastern theatre command of the People's Liberation Army and other establishments of the world's largest military power.Gen Singh and PLA commander Li Zuocheng discussed a "wide range of issues of mutual interest", said an official of the Indian embassy here.They agreed to further expand defence exchanges between the two armies, said the official.Gen Singh also met the Vice Chairman of all-powerful Central Military Commission, General Xu Qiliang.Both the officials "reiterated their desire to keep up the momentum of defence exchanges and the need to keep the borders tranquil and peaceful".Gen Singh invited both Li and Xu to visit India. Both accepted the invite and Li said he hoped to visit India soon.Gen Singh will also go to Xian and Nanjing, where he will visit key military installations and interact with General Liu Yuejun, Commander of the eastern theatre command.The eastern theatre command is one of the five zones of PLA.