UNITED NATIONS (AP) — The United States is seeking the toughest-ever U.N. sanctions on North Korea that would ban all oil and natural gas exports to the northeast Asian nation and freeze all foreign financial assets of the government and its leader, Kim Jong Un.

The U.S.-drafted resolution, circulated to council members Wednesday and obtained by The Associated Press, would also prohibit North Korea from exporting textiles and ban all countries from hiring and paying workers from the northeast Asian nation — two key sources of foreign currency.

The proposed resolution identifies nine cargo vess...