South Korea's bourse operator activated a buy-side sidecar for the KOSPI on Monday after the index spiked on news of a U.S.-Iran peace deal.
The Korea Exchange suspended program trading for KOSPI-listed shares for five minutes shortly after the market opened. The measure was triggered when the KOSPI 200 Futures index rose 5 percent or more for at least one minute.
The KOSPI rose 327.7 points, or 4.03 percent, to 8,451.32 as of 9:07 a.m. Investors bought blue-chip tech shares after U.S. President Donald Trump said the United States and Iran had reached a deal to end their months-long war and reopen the Strait of Hormuz.
A formal signing ceremony is expected to take place Friday in Switzerland. Brent crude fell 3.37 percent to US$87.3 per barrel on the news.