The company claims the Commission took the decision on the basis of a “flawed process, an inaccurate and incomplete assessment by the European Food Safety Authority and without the full support of EU member states”.
In an action that is expected to be lengthy and which is unlikely to be completed before the ban comes into place in December, it filed its case against the Commission at the EU General Court in Luxembourg.
John Atkin of Syngenta said: “We would prefer not to take legal action but have no other choice given our firm belief that the Commission wrongly linked thiamethoxam to the decline in bee health.
“In suspending the product, it breached EU pesticide legislation and incorrectly applied the precautionary principle.”
The ban was opposed by the UK farm minister Owen Paterson.