In particular, strengthening the control on " weapon-usable" fissile materials-highly enriched uranium (HEU) and separated plutonium is essential.

加强控制武器用裂变材料——高浓铀（HEU）和分离钚是极为本质的。

youdao

Until this year, Pyongyang has denied U.S.accusations it possessed a covert HEU, or highly enriched uranium program, in violation of previous agreements.

VOA: standard.2009.09.06

Current law is aimed at phasing out U.S. exports of highly enriched uranium (HEU) precisely to reduce the risk of the material being stolen or diverted by proliferating states for nuclear weapons production.

CENTERFORSECURITYPOLICY: Kyl and Schumer move to monitor uranium exports

The HEU Agreements allow for the downblending of highly enriched uranium derived from nuclear weapons to low enriched uranium for peaceful commercial purposes.

WHITEHOUSE: Notice -- Continuation of the National Emergency with Respect to the Risk of Nuclear Proliferation Created by the Accumulation of Weapons-Usable Fissile Material in the Territory of the Russian Federation | The White House

Press reports over the New Year state that Brazil is set to manufacture highly-enriched uranium (HEU) for its two nuclear power plants, and according to Samuel Faiad of the government-run Nuclear Industries of Brazil, to sell any HEU surplus on the world market.

CENTERFORSECURITYPOLICY: Next nuclear weapons problem: Brazil?