The Department for Energy and Climate Change has tweeted an infographic outlining the stages of shale gas and oil, from the exploration stage through to decommissioning.
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Bolton is viewed with contempt by almost the entire foreign policy establishment in Washington.
A top temperature today of 13 Celsius (55F).
Mr Trump tweeted that Mr McMaster has done "an outstanding job & will always remain my friend." He said MrBolton will take over on April 9.