The European Union's foreign-policy director today condemned as "deeply irresponsible" North Korea's presumed sinking of a South Korean naval corvette, after an international team concluded that Pyongyang was behind the incident, dpa reported. The conclusion by a team of experts from South Korea, the US, Australia, Sweden and Britain as to the cause of the Cheonan's sinking on March 26 has sharply raised tensions on the peninsula. "The findings of the investigation are extremely disturbing, in particular the evidence presented of North Korean involvement. Based on these findings, I strongly condemn this heinous and deeply irresponsible action," Catherine Ashton said in a statement. Investigators from the five countries concluded earlier on Thursday that there was "overwhelming" evidence of North Korean involvement in the March 26 sinking of the warship Cheonan, which killed 46 South Korean sailors. The South Korean authorities vowed to respond to the alleged attack, but called for an international diplomatic response rather than military action. North Korea denied the claims and threatened a response which could include "all-out war." South Korea had earlier vowed to take the case to the United Nations Security Council if it proved that the North had been involved in the sinking. "I commend the restraint which the government of the Republic of Korea has shown in a tense situation of national grief and outrage. The EU will consult closely with the Korean authorities and other interested parties on the appropriate response to the findings of the report," Ashton said.