The BBC reports that the Wildlife Trusts is to take legal action against the UK government over its decision to allow a pesticide that is almost entirely banned in the EU.
In 2018, the EU banned the outdoor use of neonicotinoid pesticides, which harm pollinating insects such as bees.
But following Brexit, the government approved the emergency use of one neonicotinoid to combat a crop disease.
The charity has told Environment Secretary George Eustice of their intention to challenge the decision.
In a letter to Mr Eustice, the Trusts says it will push for a judicial review unless the government can “prove it has acted lawfully”.
Multiple studies, including large-scale field trials, have found that neonicotinoids harm pollinators and aquatic life. Research has also shown that they can be linked to the wider collapse in biodiversity.
The government says it allowed the use of the neonicotinoid thiamethoxam because of the “potential danger” to the sugar beet crop from beet yellows virus, which is spread by aphids.