Britain needs a 'citizen's army' to fight the influx of invasive species, a committee of MPs has advised the government in a new report.

The Environment Audit Committee has said that 1.3 million trained volunteers are needed to identify and respond to biosecurity outbreaks, in a new scheme modelled on a system developed in New Zealand.

They would be trained to identify invasive species and either destroy them, prevent them spreading or alert authorities to new outbreaks so they can be swiftly dealt with.

The growing threat from Invasive Non-Native Species (INNS), is estimated to cost Britain’s economy £1.8 billion a year.

If the government takes these recommendations on board, the committee said the citizen's army could be set up by around 2025. The committee also called for a special border force for invasive species to be set up by 2020.

Chair of the Environmental Audit Committee Mary Creagh MP said: “INNS is one of the UK’s top five threats to the natural environment. If we’re to beat this, we need people power with an army of volunteers trained to spot and stop an invasive species before it becomes established.

“We’re witnessing changes, from climate change, that put the future of our natural landscape at risk. Oak Processionary Moth caterpillars can strip an oak tree bare as well as posing a hazard to our own health. We face losing half of the UK’s native ash trees to ash dieback within a century costing £15 billion. New regulations to halt their progress are welcome but they are too little, too late.