The research, published in the journal Proceedings of the Royal Society B, saw beehives exposed in a laboratory to food laced with the pesticides.
After 50 days the scientists found the bees had about 40 per cent less living sperm.
The NFU and other industry bodies have consistently said that field work needs to be done to establish whether the pesticides have any adverse effect in real-life conditions, including in a recent HW report on research into neonicotinoid use on plants for sale in garden centres.
NFU chief horticulture adviser Dr Chris Hartfield said: "We already know doses of neonicotinoids can have harmful sub-lethal impacts on bees – so it not surprising that when you give honeybees food laced with neonicotinoids, it can impact on their reproduction. This research is interesting, but it doesn’t show these impacts are occurring under natural field situations and it doesn’t show that neonicotinoid use is causing widespread declines in pollinator populations. Until these major gaps in our understanding are filled, the evidence is still not conclusive enough to provide clear guidance for policymakers."
Friends of the Earth said: "The focus on honeybees drones is especially interesting and new. More studies are needed to fully understand the impact of neonics on all bee species and other invertebrates such as butterflies.
"But while the science must continue the politicians already have the clear evidence they need. The UK Government must make it clear that no matter how much the pesticide firms lobby for their widespread return these chemicals will be kept out of Britain's fields."
Neonicotinoids were banned for use on flowering crops in the EU in 2013. The UK opposed the ban and allowed a limited lift of the ban in 2015, but has refused further suspensions this year