SEOUL (Reuters) - North Korea will fire across a land border with South Korea if Seoul continues its anti-North psychological campaign, the Norths official media said on Sunday ahead of an annual, joint military drill between the United States and South Korea. South Koreas military has been dropping leaflets into North Korea about democracy protests in Egypt and Libya in a bid to encourage North Koreans to think about change, although analysts remain sceptical that the move would prompt residents in the isolated state to rise up to similar protests. The on-going psychological warfare by the puppet military in the frontline area is a treacherous deed and a wanton challenge to the demand of the times and desire of all the fellow countrymen to bring about a new phase of peaceful reunification and national prosperity through all-round dialogue and negotiations, KCNA news agency said. We officially notify that our army will stage a direct fire at the Rimjin Pavilion and other sources of the anti-DPRK psychological warfare to destroy them on the principle of self-defence, if such actions last despite our repeated warning. The Rimjin Pavilion is an area in South Korea near the heavily armed Demilitarised Zone (DMZ) which separates the two Koreas. DPRK is North Koreas official name, standing for the Democratic Peoples Republic of Korea. North Korea will also be on a heightened state of alert for possible provocation during the joint military drill between the United States and South Korea which starts on Monday, KCNA said. North Korea will respond to the planned military drills with all-out war if there is any provocation, it added. If the aggressors launch provocation for a local war the world will witness unprecedented all-out counteraction on the part of the army and people of the DPRK, KCNA said, adding that it could use its nuclear capability as needed. Pyongyang has often raised the rhetoric and has wielded its nuclear capability threat in the past, but analysts do not expect it to launch a nuclear device. North Korea reacts very sensitively as it thinks the power of psychological leaflets is bigger than that of a nuclear bombing, a South Koreas news agency Yonhap quoted a local analyst as saying.