ESSINGTON, Pa. - New Jersey U.S. Sen Bob Menendez says Republican presidential candidate Donald Trump's comments about Russia exposing Hillary Clinton's emails are an "act of treason."

The Democrat says that the United States' role in the world matters and that he can't accept someone who thinks Russia is a friend or who would negotiate with North Korea.

He was the ranking member of the Senate Foreign Relations Committee before voluntarily stepping down last year after he was indicted on corruption charges. He has pleaded not guilty and faces trial later this year.

Trump says he was using sarcasm when he prodded Russia to unearth Clinton's missing emails

Menendez spoke Thursday at the state Democrats' breakfast during an impassioned speech introducing Sen. Cory Booker.