Below are my five tips for Labour candidates and MPs on how to deal with the Green Party.

1. Remind people that the only effect of voting for the Green Party (not Green - Labour is Green) in your constituency is to help the Tory win and help the Conservatives win a majority nationally.

2. Remind people of Labour's record in Government. The first country in the world to pass a legally binding Climate Change Act. Our Marine Act set the international standard for marine conservation. A whole swathe of environmental and other action by the last Labour Government on waste, air quality, sustainable transport including cycling and walking, protecting the natural environment and biodiversity, animal welfare and much else. We were the Greenest government ever.

3. Tell people how Labour have opposed this Government tooth and nail - nowhere more so than on the Tory and Lib Dem's abandonment of the environmental and sustainability agenda. From fracking to betraying the renewables sector and through all the policies in between Labour has opposed this Government every step of the way.

4. The Green Party, rather like Nick Clegg's Liberal Democrats before the last election, offer a list of impossibilist, undeliverable and downright mad policies that they know they'll never be in a position to have to implement. Labour meanwhile has a realistic programme for social and environmental justice and our Greenest leader ever.

5. The Green Party supports UKIP and the Tories' policy of holding a referendum on our membership of the EU in the next Parliament. Is this really the priority for Britain over the next few years? An EU referendum would completely dominate our politics. It would be a massive distraction, given the huge challenges the next Government is going to face tackling growing inequality and environmental degradation and much else.