The United States today announced new sanctions against North Korea's leadership, and warned of serious consequences if it again attacked the South.
Relations across the divided peninsula have turned increasingly hostile after South Korea accused the North of sinking one of its warships in March, killing 46 sailors.
US secretary of state Hillary Clinton said Washington was ready to return to international talks over North Korea's nuclear weapons programme if Pyongyang sent a "positive signal", but that there had been none so far.
"We are aiming very specifically, after much intensive research built on what was done before but not limited to that, to target the leadership, to target their assets," Ms Clinton told a news conference in Seoul with US defense secretary Robert Gates and their South Korean counterparts.
She insisted the additional sanctions were not aimed at ordinary North Koreans, who make up one of the world's poorest societies and whose stumbling economy is already largely sealed off from the outside world because of previous punishments over nuclear and missile tests.
China, the North's only major ally, expressed "deep concern" after the United States and South Korea said they would start large-scale joint military drills on July 25th. State television yesterday showed the Chinese navy conducting its own exercises.
Mr Gates called for a resumption of military-to-military ties with China, suspended earlier this year over planned US arms sales to Taiwan.
North Korea's economy is mainly subsistence in nature with few factories able to operate at even a third their capacity and farms lacking fertiliser and seed to grow crops. A disastrous decision to issue a new currency last year left many without their life savings and many North Koreans conduct illicit business by travelling to China.
"The sanctions announced by the US will not really affect the North Korean economy as all possible sanctions have already been imposed," said Paik Haksoon, a senior fellow at the Sejong Institute. "China is cooperating with North Korea economically because the stability of North Korea is a key national interest of China."
The South Korean and US foreign and defence ministers warned of "serious consequences" if there were any future North Korean attacks against the South.
A South Korean-led investigation team concluded a North Korean submarine fired a torpedo which sank the South Korean corvette Cheonan in March. North Korea denied it had anything to do with the Cheonan's sinking.
The United States and South Korea on July 25th will conduct joint naval and aerial exercises off the east coast of the peninsula. The aircraft carrier the USS George Washington arrived in South Korea's second-biggest city, Busan, today.
Earlier in the day, Clinton and Gates made an unusual joint visit to the heavily defended demilitarised zone (DMZ) that divides the two Koreas amid a warning the peninsula faced a dangerous new period.
Reuters