Task: Question Answering
Input (English): Passage: The on-again, off-again armistice negotiations continued for two years, first at Kaesong, on the border between North and South Korea, and then at the neighbouring village of Panmunjom. A major, problematic negotiation point was prisoner of war (POW) repatriation. The PVA, KPA, and UN Command could not agree on a system of repatriation because many PVA and KPA soldiers refused to be repatriated back to the north, which was unacceptable to the Chinese and North Koreans. In the final armistice agreement, signed on 27 July 1953, a Neutral Nations Repatriation Commission, under the chairman Indian General K. S. Thimayya, was set up to handle the matter. Question: When was the armistice agreement finally signed?
Output (English): 27 July 1953