Article published on the 2009-06-08 Latest update 2009-06-08 14:26 TU
The White House said that it was engaged in "all possible channels" to ensure the release of Laura Ling and Euna Lee.
Secretary of State Hilary Clinton called the charges baseless and said the journalists should be allowed to return home.
New Mexico Governor Bill Richardson, a former US ambassador to the United Nations who has negotiated with North Korea, told the television network ABC, "now a legal process ends and political negotiations can begin".
Meanwhile, Reporters Without Borders, based in Paris, said it was "appalled" by the sentence. They "are much more severe than anything we had imagined", the group said.
"The sentences were clearly designed to scare journalists trying to do investigative reporting in the border area between China and North Korea, which is ranked as Asia's worst country in the Reporters Without Borders press freedom index", it added.
North Korea's news agency, the KCNA, said Ling and Lee were convicted for illegal entry and unspecified "grave crime" at the end of a five-day trial. They work for the California-based web television station Current TV and were researching a story on North Korean refugees.