BRUSSELS • European Union countries deadlocked on Thursday on the future of weedkiller glyphosate that some experts say causes cancer, with the European Commission urging them to reconsider its proposal to allow its use to continue for five years.

Europe has been wrestling for two years over what to do with the chemical, a key ingredient in Monsanto Co.'s top-selling weedkiller Roundup.

The chemical has been used by farmers for more than 40 years, but its use was cast in doubt when the World Health Organization's cancer agency concluded in 2015 it probably causes cancer.

The European Chemical Agency said in March this year, however, there was no evidence linking it to cancer in humans.

On Thursday, the European Union's 28 countries failed to approve or reject the Commission's proposal for a five-year extension to the license allowing glyphosate to be used.

Fourteen countries voted in favor, nine against and five abstained, not enough to secure a "qualified majority" under EU voting rules, the Commission said, adding that it would resubmit its proposal by the end of November, before the current authorization expires on Dec. 15.