Berkshire Hathaway Inc's Warren Buffett said on Thursday he expected the dollar to get weaker and said that South Korea's stock market was still more attractively valued than other world markets.

Buffett, who was making a one-day trip to Korea after a visit to China, said Berkshire Hathaway continued to seek good businesses, which will get cheaper in markets if problems from the US subprime mortgage crisis continues.

"We are still negative on the dollar. We bought stocks in companies that are earning their money in other currencies," he said to reporters during a visit to unlisted Korean company TaeguTech.

"In the UK for example, we bought stocks in Tesco. We are gaining foreign currency exposure that we like."    

The US currency has lost 23 percent against the South Korean won since the end of 2003, hit by accumulating current account surpluses in South Korea and a steady inflow of portfolio investment into the country's financial markets.

International Monetary Fund Managing Director Rodrigo Rato said on Monday the U.S. currency was still overvalued and that there was room for further depreciation.

Buffett was sanguine about the impact on Berkshire's investments arising from the subprime mortgage crisis in the United States. While he acknowledged it had been having an impact, he added that potential investment candidates could become cheaper amid market turmoil.

"In six months, or one or two years, the problem in the subprime mortgage, problem in consumers and their buyings in the US may still be there, but this does not have any impact on what we do. We are looking for good businesses, and if some bad temporary news makes a business more available, then we do not care at all."

Omaha, Nebraska-based Berkshire Hathaway owns more than 70 businesses and has some $100 billion of stock and bond investments. The company also has as a subsidiary TaeguTech, which makes cutting tools and tungsten powders. - Reuters