president donald trump set sign order greatly reduce role climate change play decision make across u.s. government bloomberg report cite person familiar administration plan order could sign week aim reverse former democratic president barack obama 's broad approach address climate change report say bloom.bg/2nkdvko directive urge u.s. environmental protection agency undo clean power plan bloomberg report say clean power plan obama centerpiece initiative combat climate change require state slash emissions carbon dioxide never implement due legal challenge launch several republican state accord report measure would direct u.s. regulators rescind obama-era regulations limit oil industry emissions methane potent greenhouse gas order also involve reconsideration government use metric know social cost carbon weigh potential economic damage climate change bloomberg report tuesday trump long signal intention reverse obama climate-change initiatives republican president vow plan overhaul green regulation would jeopardize america water air quality reuters report early month white house propose slash quarter epa budget target climate-change program design prevent air water pollution like lead contamination bloomberg report say change could happen immediately others could take years implement trump drop climate change environmental review bloomberg