South Korea today announced plans to spend billions on sophisticated technology to counter the perceived threat of a North Korean nuclear attack, according to dpa. The defence ministry, reacting to the latest rocket tests by North Korea, said it would be budgeting a total of 178 trillion won - around 140 billion dollars. This would be to protect strategically important buildings from electromagnetic pulses which could be generated by nuclear explosions. The spending was part of mid-term defence planning from 2010 to 2014, the ministry said. An earlier ministry statement Friday said North Korea may have wanted to directly provoke South Korea with its latest rocket tests. The launch of four short-range rockets was obviously done with relations between the two Koreas in mind, ministry spokesman Won Tae Jae was quoted as saying by the national news agency Yonhap. "Unless it is a mid-range missile or a longer-range one, we believe it is aimed at South Korea," the spokesman said. p In a conflict etween the two countries short-range rockets would be the most useful weapons, he added. On Thursday, the North Korean military launched four short-range rockets in the direction of the Sea of Japan within a period of several hours. Reports in the South Korea media said government officials in Seoul believe they were anti-ship rockets with a range of 120-160 kilometres. The US also condemned the testing of the rockets. State Department spokesman Ian Kelly said on Thursday in Washington that the launches were a further provocation. Following a nuclear test by North Korea in May, the United Nations Security Council three weeks ago tightened sanctions against North Korea, requiring ships travelling to and from the country to be checked for weapons and nuclear materials.