WASHINGTON (REUTERS) - The White House urged North Korea on Saturday to release Merrill Newman, an 85-year-old United States (US) veteran of the Korean War who has been held in North Korean custody since last month.

"Given Mr Newman's advanced age and health conditions, we urge the DPRK to release Mr. Newman so he may return home and reunite with his family," said Ms Caitlin Hayden, a spokesman for the White House National Security Council.

The White House also urged North Korean authorities to release Kenneth Bae, an American who has been held in the country for more than a year.

"We remain deeply concerned about the welfare of the US citizens held in custody in the DPRK," Ms Hayden said in a statement.