Europe's debt crisis was picked as the biggest threat facing the South Korean economy amid spreading concerns that Greece may exit the euro zone, a poll showed Tuesday.

According to the survey of 41 experts by the Federation of Korean Industries (FKI), 73 percent of the respondents picked the European fiscal crisis as the biggest threat to the South Korean economy in the second half of this year.

This was followed by slower economic recovery in the United States, which 15 percent of experts viewed as a threat. Economic slowdown in emerging countries and higher commodity prices ranked third and fourth risk factors to the economy in the survey.

The survey came amid deepening concerns over the European debt crisis. Failure to form a coalition government in Greece boosted fears that the European country may be forced out of the euro zone, while the newly elected French President was against strong austerity plans. Amid stronger external uncertainties, foreigners sold local stocks over the past 14 sessions.

On the domestic front, excessive household debt was picked as the biggest threat to the South Korean economy. More than half of the respondents viewed as the biggest risk factor the nation's household debts that topped 900 trillion won (770.88 billion U.S. dollars) as of the end of 2011.

Meanwhile, the respondents expected the South Korean economy to grow 3.3 percent in 2012, lower than a 3.5 percent growth estimated by the Bank of Korea (BOK), the International Monetary Fund (IMF) and the Organization for Economic Cooperation and Development (OECD).