Seoul - Top aides to the leaders of North and South Korea will meet at the Panmunjom truce village straddling their border on Saturday, the South said, raising hopes for an end to a standoff that put the two sides on the brink of armed conflict.The meeting is due to take place half an hour after North Korea's previously set ultimatum demanding that the South halt its loudspeaker propaganda broadcasts along the border or face military action.South Korean President Park Geun-hye's national security adviser and her unification minister will meet with Hwang Pyong So, the top military aide to North Korean leader Kim Jong Un, and a senior official who handles inter-Korean affairs at 18:00 Seoul time (09:00), the Blue House said.Pyongyang made an initial proposal on Friday for a meeting, and Seoul made a revised proposal on Saturday seeking Hwang's attendance, Kim said. He left the briefing without taking questions.‘Quasi-state of war’Tension on the Korean peninsula has been running high since an exchange of artillery fire on Thursday, prompting calls for calm from the United Nations, the United States and the North's lone major ally, China.North Korea, technically still at war with the South after their 1950-53 conflict ended in a truce, not a peace treaty, had declared a "quasi-state of war" in front-line areas and set the deadline for Seoul to halt the broadcasts from loudspeakers placed along the border."The situation on the Korean peninsula is now inching close to the brink of a war due to the reckless provocations made by the South Korean military war hawks," the North's KCNA news agency had said earlier.Seoul had said it would continue the broadcasts unless the North accepted responsibility for landmine explosions this month in the Demilitarised Zone (DMZ) that wounded two South Korean soldiers. Pyongyang denies it planted the mines.South Korean Vice Defence Minister Baek Seung-joo said on Friday his government expected North Korea to fire at some of the 11 sites where Seoul has set up loudspeakers.The United States, which has 28 500 military personnel based in South Korea, said on Friday it had resumed its annual joint military exercises there after a temporary halt to co-ordinate with Seoul over the shelling from North Korea.US reaffirms commitment to SouthThe drills, code-named Ulchi Freedom Guardian, began on Monday and run until next Friday. North Korea regularly condemns the manoeuvres as a preparation for war.Four South Korean and four US fighter jets flew in a joint sortie over the South on Saturday, an official at the South's office of the Joint Chiefs of Staff said by telephone.The top US military officer, General Martin Dempsey, reaffirmed Washington's commitment to the defence of South Korea in a telephone call between the chairpersons of the two countries' Joint Chiefs of Staff, the South Korean side said.North and South Korea have often exchanged threats over the years, and dozens of soldiers have been killed in clashes, yet the two sides have always pulled back from all-out war. Analysts had expected this crisis eventually to wind down.North-South ties have been virtually frozen since the deadly 2010 sinking of a South Korean warship. North Korea denies it was involved.South Korea began blasting anti-North propaganda over the DMZ on August 10, resuming a tactic both sides had stopped in 2004, days after the landmine incident.North Korea resumed its own broadcasts on Monday and on Thursday, according to Seoul, launched four artillery shells into South Korea in apparent protest. The South fired back 29 artillery rounds.Pyongyang accused the South of inventing a pretext to fire into the North.Neither side reported casualties or damage.North Korea has been hit with UN and US sanctions because of its nuclear and missile tests, moves that Pyongyang sees as an attack on its sovereign right to defend itself.