Standard Chartered bank said Wednesday net profit fell more than 16 percent in 2013 and warned of a difficult first half for 2014 following significant challenges for its South Korean operations. The London-based lender, which makes 90 percent of its profits in Asia, the Middle East and Africa, said net profit was $3.99 billion last year, down 16.65 percent from $4.79 billion in 2012. Standard Chartered's South Korean retail bank suffered a $1.0 billion write-down in its value, and produced lower revenue with higher bad loans during the year, culminating in a $162 million operating loss. Overall operating income fell one percent to $18.67 billion in 2013, compared to the previous year, while annual profit before tax was down 11 percent to $6.06 billion. The results follow a decade in which the bank posted consecutive full-year profits. "2013 was a challenging year, for the industry and for Standard Chartered," said its chairman John Peace in a statement. The bank said bad loans across its operations had increased by 35 percent year-on-year to $1.62 billion. "While our clients have remained very active, the overall outcome for the group has not been as good as we would have liked," Peace said. Consumer banking income for the group grew by two percent to $7.18 billion, while wholesale banking income fell two percent to $11.49 billion. - Weak first half for 2014 - The bank's chief executive Peter Sands warned of a weak performance for the first half of 2014 following weak growth in the past quarter. "Given the weakness of our performance in the fourth quarter of 2013, we anticipate that the first half of 2014 may prove challenging," Sands said in the statement. "We do not expect to deliver double-digit income growth over the next couple of years, given various pressures, not least Korea," he said. "However, we haven't abandoned double-digit growth as a longer-term aspiration." Richard Hunter, head of equities at Hargreaves Lansdown Stockbrokers, said the group was "bucking the trend of the wider market", with an outlook that "offsets a disappointing year by its own standards". The bank said income from consumer banking for Hong Kong rose 11 percent to $1.56 billion, while income for the same sector from the Middle East and other South Asian regions was up six percent at $801 million. Its income for consumer banking in Africa increased by 10 percent to $529 million with Kenya being its largest consumer banking income-generator, growing 11 percent in that sector alone. Income from consumer banking in China grew eight percent to $321 million, but fell 12 percent to $1.05 billion in South Korea. In November last year the bank lowered its annual revenue growth target to a range of seven to nine percent for the next couple of years, from an initial forecast of at least 10 percent. -- Dow Jones Newswires contributed to this report --