Credit loans extended by the nation's five major banks jumped in the first 15 days of August, official data showed Monday, due apparently to government measures that tightened mortgage lending rules.

South Korea tightened rules for home mortgages from Aug. 2 to rein in rapidly growing household debt and curb property speculation.

As of last Wednesday, the outstanding balance of credit loans by the five retail banks, including KB Kookmin Bank and Shinhan Bank, stood at 93.1 trillion won ($81.8 billion), up 588.2 billion won from the end of July, according to the data by the Financial Supervisory Service. 

If the trend continues, credit loans would grow by about 1.2 trillion won by the end of this month. It would mark one of the fastest months of growth in credit loans.

The sharp growth this month came after more people appeared to have taken out loans on credit to help buy homes because of tighter mortgage regulations.

Although credit loans are not allowed to be used for buying a home, there are some financial loopholes that can be used.

In the latest bid to rein in the overheating housing market, the government designated all 25 wards in Seoul and two cities -- Sejong and Gwacheon, south of Seoul -- as "speculative or overheated speculative districts."

In particular, 11 districts in Seoul and Sejong were designated special regions subject to far tougher taxes, financial regulations and state scrutiny.

The loan-to-value and debt-to-income ratios were cut to 40 percent in all those districts, limiting mortgages to 40 percent of their property value and a maximum 40 percent of their income for mortgage payments.

Zhin Woong-seob, governor of the FSS, said Monday that the financial regulator will step up an on-site inspection at banks to check whether borrowers use credit loans or other debt to buy homes.

Debt owed by small merchants grew by 20.3 trillion won during the first half of this year, compared with a growth of 15.6 trillion won for the same period last year, according to the FSS.

Zhin said the financial regulator will "sternly deal with" applications of loans to avoid the impact of the tougher lending regulations.

However, Zhin expected the growth pace of total household debt to slow down in the wake of the tougher measures. (Yonhap)