The U.S. government has officially taken a silent policy towards the nuclear weapons ambitions of the state of Israel, while being exceedingly vocal against proliferation of such weapons in the countries of Iran and North Korea. Until 2005 when the program was cancelled, it was violating its own non-proliferation treaties in the pursuit of so-called nuclear bunker busters. The 2003 invasion of Iraq by the U.S. was done, in part, on indications that Weapons of mass destruction were being stockpiled (later, stockpiles of previously undeclared nerve agent and mustard gas shells were located in Iraq), and the Bush administration said that its policies on proliferation were responsible for the Libyan government's agreement to abandon its nuclear ambitions.