UN Secretary-General Ban Ki-moon on Sunday expressed extreme concern over the increasing risk of the spillover of the Syrian unrest to Lebanon, urging respect for the national sovereignty and territorial integrity of all countries in the region. \"The secretary-general is deeply concerned by the acknowledged increased participation in the fighting in Syria by Hezbollah, as well as by the risk of spillover in Lebanon, which has witnessed growing tension over the past week,\" said a statement released by Ban\'s spokesperson. \"All in the region should act responsibly and work towards lowering rhetoric and calming tensions in the region.\" As preparations are ongoing for the international conference on Syria, Ban called on all countries, organizations and groups immediately to cease supporting the violence inside Syria and instead to use their influence to \"promote a political solution to Syria\'s tragedy,\" said the statement, reported Xinhua news agency .