Member states will vote on Friday on an almost complete ban on the use of neonicotinoid insecticides across the EU.
Scientific studies have linked their use to the decline of honeybees, wild bees and other pollinators.
The move would represent a major extension of existing restrictions, in place since 2013.
Manufacturers and some farming groups are opposed, saying the science remains uncertain.
Neonicotinoids are the most widely used class of insecticides in the world, but concerns about their impact on bees have been reinforced by multiple research efforts, including so-called "real world" trial results published last year.
Change of heart
Back in 2013 the European Union opted for a partial ban on the use of the three chemicals in this class: Imidacloprid, clothianidin and thiamethoxam.
The restrictions applied to crops including maize, wheat, barley, oats and oil seed rape. The new Commission proposal would go much further, meaning that almost all outdoor uses of the chemicals would be banned.
The action has been driven by a recent report from the European Food Safety Authority (Efsa), which found that neonicotinoids posed a threat to many species of bees, no matter where or how they are used in the outdoor environment.
Another key element that has pushed the Commission to hold a vote has been the UK's change of heart on the use of these insecticides. Environment Secretary Michael Gove announced last November that the UK would now support further restrictions.
"I think it has helped the dynamic," Franziska Achterberg from Greenpeace told BBC News.
"It has helped sway Ireland definitely, and then lately, the Germans, the Austrians and the Dutch. I think the fact the UK had come around was a good signal for them as well, that they could not stay behind."
During the partial ban, some countries including the UK were given permission to use neonicotinoids for short periods. However, the EU Commission is now signalling that it is seemingly intent on pushing the proposal through as it stands.
"Several countries have said they want exemptions on sugar beet for example," said Sandra Bell from Friends of the Earth (FOE).
"So far the Commission have been very strong on this, because they say the Efsa evidence backs the extension of the ban to sugar beet and therefore they are following the science and won't put in an exemption for a compromise."
Growers will be free to use neonicotinoids in greenhouses across the EU, despite some environmental groups having reservations about the chemicals leaching into water supplies. Other neonicotinoids including thiacloprid and sulfoxaflor will continue to be exempt from the ban.
No benefits for bees
Many farmers are unhappy about the proposed increase in restrictions, saying they do not believe they are warranted on scientific grounds and that the existing partial ban has not delivered results.
"The Commission hasn't been able to find that these restrictions have delivered any measurable benefits for bees," said Chris Hartfield from the National Farmers' Union (NFU).
"That has been a big question for us, and if we can't be certain they can deliver measurable benefits why are we doing this?"
The Commission's proposal needs to reach a qualified majority to go forward, meaning 55% of states representing 65% of the EU population will have to support the measure.
If that fails, the Commission will likely take it to an appeals committee within weeks. If that also fails to produce a result, then the Commission can unilaterally impose their ruling.
British farmers say that if the proposal goes ahead, it could have significant impacts on the types of crops grown across the Continent.
"The irony of the current restrictions is that it has led to the decline of oil seed rape being grown in the UK and that's reflected across the whole of Europe," said Chris Hartfield from the NFU.
"We're not decreasing our consumption of that product, we are just importing it from outside Europe, where it is often treated with neonicotinoids - I would expect to see that continue."
There is a cautious optimism among environmental campaigners that the measure will go through, either today or in the very near future.
Some believe that it heralds a new era for EU farmers where the needs of the environment are seen as more important than production.
"It's a significant indication that we need a different form of farming across Europe that farms with nature and not against it," said FOE's Sandra Bell.
"The ban on neonicotinoids, if it happens, could be a really important step towards a more general questioning of the use of pesticides and the harm they are doing to our environment."