WASHINGTON -- U.S. Sen. Robert Menendez, the top Democrat on the Senate Foreign Relations Committee, said Sunday that he hoped President Donald Trump can succeed in getting North Korea to end its nuclear program.

Menendez, D-N.J., speaking on ABC's "This Week," expressed concern that Trump has not done the necessary preparation for his historic summit with North Korean leader Kim Jong Un.

"The president has gone into a high wire act without a safety net," Menendez said. "While we applaud robust diplomacy, the preparation for this type of a summit to test the proposition of what Kim Yong Un is willing to do or not has not taken place. This is a bit of a risk."

Menendez and other Senate Democrats told Trump in a letter last week that any deal should require North Korea to dismantle its nuclear, chemical, and biological weapons; end the production of uranium and plutonium for military purposes and dismantle its test sites and research facilities; do away with its ballistic missiles and programs; and agree to on-site inspections.

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