The statement said Ms Ling suffered from an ulcer and that Ms Lee had a four-year-old daughter who was "displaying signs of anguish".
"We believe that the three months they have already spent under arrest with little communication with their families is long enough," the statement said.
After a short trial, the North's official news agency KCNA said on Monday that the women had committed a "grave crime" and would be sentenced to 12 years of "reform through labour".
KCNA gave no further details.
The pair were arrested by North Korean guards on 17 March while working on the China-North Korea border on a story about refugees for California-based internet broadcaster Current TV.
Some reports have suggested that the women did not stray over the border but were seized by North Korean border guards who crossed into Chinese territory.
The pair have been held in detention since their arrest.
Tensions have increased in the region since North Korea conducted a nuclear test in May and then test-fired several missiles.
Another long-range missile test is believed to be planned for later this month.
The UN Security Council is discussing tightening sanctions against Pyongyang, and Mrs Clinton said on Sunday that the US was considering reinstating North Korea in its list of state sponsors of terrorism.
Analysts believe the North may try to use the women as a bargaining chip in negotiations over their nuclear programme.
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