South Korean companies, led by construction firms, are expecting to find more business opportunities in Iran on hopes that economic sanctions on Tehran may be lifted in the coming months, industry sources said Friday.

On Thursday, the United States and five other Western powers reached a tentative agreement which will lift crippling economic sanctions against Tehran. If the deal is ratified before July, economic sanctions on the oil-rich country will be lifted, providing a slew of business deals to foreign firms.

"Although South Korea's exports to Iran are less than 1 percent of its total outbound shipments, its growth potential is huge next to that of Saudi Arabia," said Cho Hak-hee, an analyst at the Korea International Trade Association (KITA).

"If economic sanctions are lifted, our exporters would find good business opportunities in the country."

Analysts said a series of construction and infrastructure projects may be up for grabs for South Korean firms.

In the past decades, South Korean builders had clinched deals worth $12 billion with Iran, but since 2009 there have been few deals due to the economic sanctions that the United Nations imposed for its nuclear weapons program in 2010.

"Until 2000, Iran was the fourth-largest market for South Korean construction firms after Saudi Arabia, Libya and Iraq ... but the nuke deal this time would pave the way for South Korean firms to tap deeper into the nation," said Kim Jong-kuk, the manager of the Middle East division at the International Contractors Association of Korea.

The association projected Iran's construction market to reach $154 billion in 2016, sharply up from $88.7 billion in 2013.

Steelmakers and airlines may be in line to benefit from an expected lifting of the economic sanctions, according to Chun Jung-hoon, an analyst at Kiwoo Securities.

"Korean steel plates would gain a footing in Iran as automakers there import a huge chunk of parts," said the analyst, adding that South Korean products accounted for 24.3 percent of Iran's auto steel sheets in 2012, but its share fell to 15.7 percent in 2013 due to the economic sanctions.

Airlines are also positioned to benefit from low oil prices as Iran's crude oil would flow into the global market, further driving down already low oil prices.

South Korean refiners are also expecting to diversify their import lines, which would eventually help them improve their earnings. Last year, only two refiners -- SK Innovation Co. and Hyundai Oilbank Inc. -- imported Iranian oil.

Their combined imports in 2011 reached 87.18 million barrels worth $9.2 billion, but tumbled to 44.92 million barrels worth $4.5 billion in 2014, according to industry data.

Meanwhile, South Korean banks may see their businesses related to trade with Iran flourish if the economic sanctions are lifted.

Settlements with Iranian trade have been done through only two state-run banks -- Woori Bank and the Industrial Bank of Korea.

Banking sources said the focus of attention is also on whether South Korea will allow the Seoul branch of Iran's Bank Mellat to resume operations. In 2010, Seoul suspended its operation following the U.N. sanctions. (Yonhap)