WASHINGTON -- New U.S. sanctions will punish eight North Korean banks and 26 bank workers living abroad, the Trump administration announced Tuesday, in the first use of new sanctioning powers granted by U.S. President Donald Trump.

The sanctions rely on an executive order Trump signed last week to target North Korea's access to the international banking system. They come as the United Nations has also recently passed its toughest sanctions package targeting North Korea.

Trump, speaking in the Rose Garden on Tuesday, said North Korea must no longer be allowed to "threaten the entire world with unthinkable loss of life."

"All nations must act now to ensure the regime's complete denuclearization," Trump said.

The eight banks are all in North Korea. The Treasury Department said the 26 individuals are North Korean nationals employed by those banks. Of the 26, 19 of them live in China, while three live in Russia and two each in Libya and the United Arab Emirates.

"This is a clear message to Chinese banks: We can find these individuals, so can you," said Anthony Ruggiero, a senior fellow at the Washington-based Foundation for Defence of Democracies, which advocates for tough sanctions on North Korea.

The sanctions are part of a Trump administration effort to show it's still committed to using economic pressure and diplomacy to resolve the North Korea nuclear crisis, rather than the military threat that Trump has repeatedly issued. After Trump tweeted that North Korean leader Kim Jong Un "won't be around much longer, his administration clarified on Monday that the U.S. is not seeking his overthrow.

Secretary of State Rex Tillerson said Tuesday that diplomacy was still the preferred option. And Treasury Secretary Steven Mnuchin, in announcing the new sanctions, described them as part of the broader effort to isolate North Korea.

"We are targeting North Korean banks and financial facilitators acting as representatives for North Korean banks across the globe," Mnuchin said.

The U.S. also used an additional designation to emphasize that two banks in North Korea are actually part of Kim's government: the Foreign Trade Bank of the Democratic People's Republic of Korea and the Central Bank of Democratic People's Republic of Korea. Both banks had been previously targeted under earlier sanctions authorities.