WASHINGTON - US President Barack Obama held a phone conversation with South Korean President Lee Myung-bak following the death of top leader Kim Jong-il of the Democratic People's Republic of Korea (DPRK), the White House said Monday.

Obama reaffirmed US strong commitment to the stability of the Korean Peninsula and the security of South Korea, the White House said in a statement.

"At midnight tonight, President Obama spoke with Republic of Korea President Lee Myung-bak to discuss the situation on the Korean Peninsula following the death of Kim Jong-il," said the White House statement.

"The president reaffirmed the United States' strong commitment to the stability of the Korean Peninsula and the security of our close ally, the Republic of Korea," said the statement.

The White House said the two leaders agreed to stay in close touch as the situation develops and agreed they would direct their national security teams to continue close coordination.

Kim Jong-il passed away Saturday at the age of 69 "from a great mental and physical strain," the DPRK's official KCNA news agency reported on Monday.

Kim died "from a great mental and physical strain at 08:30 (2330 GMT Friday) December 17, 2011, on train during a field guidance tour," said the report.

Kim, who had received medical treatment for his cardiac and cerebrovascular diseases for a long period, suffered "an advanced acute myocardial infarction, complicated with a serious heart shock" on the train, it added.