The KOSPI rose above 6,600 during trading for the first time, pushing the market value of South Korea's stock markets above 6,000 trillion won.

On April 27, the KOSPI was up 115.78 points, or 1.79 percent, at 6,591.41 as of 10:12 a.m. compared with the previous session's close. It climbed as high as 6,603.01 in intraday trade, setting a fresh record.

The Kosdaq was up 19.77 points, or 1.64 percent, at 1,223.61 at the same time. With the KOSPI and Kosdaq rising together, the total market capitalisation of South Korea's stock markets exceeded 6,000 trillion won for the first time.

According to the Korea Exchange, total market capitalisation stood at 6,032 trillion won as of that day. By market, the KOSPI was 5,354 trillion won, the Kosdaq was 674 trillion won and the Konex was 3 trillion won.

South Korean stocks are extending gains as expectations of improved semiconductor conditions driven by growth in the artificial intelligence (AI) industry, improved earnings at major listed companies and the government's stock market revitalisation policies come together.

The KOSPI has been repeatedly setting record highs this year, and the Kosdaq is also at a high level since the dotcom bubble in the early 2000s.

In terms of flows, foreign and institutional investors led the rise. In the main board market, retail investors were net sellers of 592.8 billion won, while foreign and institutional investors were net buyers of 78.8 billion won and 511.7 billion won, respectively.

Among the biggest stocks by market value, SK Square rose more than 7 percent and SK Hynix gained in the 5 percent range. Hyundai Motor rose in the 2 percent range, and Samsung Electronics, HD Hyundai Heavy Industries and Samsung C&T also gained more than 1 percent.

In contrast, LG Energy Solution fell in the 2 percent range, while Samsung SDI and Hanwha Aerospace also dropped more than 1 percent.

On the Kosdaq, Rainbow Robotics rose more than 12 percent and ABL Bio gained in the 8 percent range. Samchundang Pharm rose more than 7 percent, while LigaChem Bio recorded gains in the 4 percent range.

As domestic market capitalisation has risen rapidly, the ratio of market capitalisation to nominal gross domestic product (GDP) has also increased. Given South Korea's nominal GDP is around 2,500 trillion won, domestic market capitalisation is at a level above twice GDP.

Based on the so-called Buffett index, which divides market capitalisation by GDP, debate over overheating could also be raised. Still, the industry sees room for further gains if the trend of improved earnings continues, centred on semiconductor and AI-related companies.

Its standing in global markets is also growing. South Korea's market capitalisation has climbed to ninth in the world this year after surpassing Switzerland, Germany, Taiwan and France in turn. The possibility of overtaking the Saudi Arabian and Canadian stock markets has also been mentioned.