By Sybille de La Hamaide

A prolonged drought is threatening sugar beet output in France, the EU's largest producer, with no rain forecast in key growing regions over the next two weeks, the head of French sugar beet growers' association CGB said.

Concerns over European sugar beet crops, compounded by the impact of the El Nino weather pattern in Asia, have helped drive a rally in sugar markets, with white sugar prices hitting a 9-1/2-month high on Wednesday. They had slumped to a more than five-year low earlier this year on hefty supplies, hitting sugar makers' profits.

"Water is critical for sugar beets. If it does not rain in the coming two weeks it will be catastrophic," Franck Sander told Reuters.

Meteo France sees no rain on the sugar beet plains around Paris and in northern France until at least July 14.

So far the situation is uneven, with beets showing dry leaves in some fields while others are holding up better, Sander said.

French farmers are also worried about the spread of yellows disease after heavy aphid infestations earlier in the season.

The virus ravaged crops in 2020 after the European Union banned some neonicotinoid pesticides used to protect crops, citing evidence they bees.

France granted temporary exemptions in 2021 and 2022 after farmers and sugar producers harmed said the ban threatened the industry's viability. The exemptions were later struck down by France's Conseil d'Etat after a ruling by the EU's top court.

Parliament is debating a new exemption this week as an amendment to a broader farm bill. The farm minister said she was not opposed to the measure but would prefer it to be debated separately to reduce the risk of the wider bill being rejected.

A final decision is expected later this month. However, it would come too late to affect this year's crop, as aphids typically infect plants in spring and symptoms emerge in summer.