Step one: Labour HQ texts everyone on their mailing list asking them to send an automated tweet accusing Zac of lying:

Step two: A not so subtle fake Twitter storm begins:

Of course, flip-flopping Sadiq once said Londoners should not oppose building on the greenbelt because “there is a finite space, we are an island last time I checked”. Also, coordinated Twitter whinges, what is this, 2014?