It was David Cameron who originally said "vote blue, go green", but it has fallen to Boris Johnson to be the Conservative Prime Minister having to put green measures into action.

       As COP26 gets underway, Mr Johnson has stressed the importance of coming away from the summit with serious commitments from world leaders.

       His reputation for leadership on the world stage could be at stake.

       But Mr Johnson is also facing significant pressure from his own party. Around 40 Conservative MPs have formed the Net Zero Scrutiny Group to warn of the high costs of implement the measures necessary for achieving the 2050 goal.

       Watch the full analysis by The Telegraph's Deputy Political Editor Lucy Fisher in the video above.

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