The nominee to the top U.S. post for East Asian and Pacific Affairs said that the U.S. will not ease pressure on North Korea based only on its pledge to denuclearize.

David Stilwell, nominee for assistant secretary of state for East Asian and Pacific affairs, made the remarks during his confirmation hearing on Wednesday before the Senate Foreign Relations Committee. 

Stilwell said Washington has been fooled enough times, so the steady pressure will continue to have an effect, adding the U.S. is not going to pull back just on the North's word. 

He added the U.S. pressure campaign against the North seems to be having a very positive effect, citing a lack of any nuclear tests or provocations from the North for the past two years. 

In a written statement ahead of the hearing, the nominee described the U.S. alliance with South Korea as "ironclad," saying it has only strengthened as they coordinate more closely to achieve the final, fully verified denuclearization of North Korea.