"The losses could be greater," Pablo Resco, crop technician for farmers' union COAG said.

Spain has had only light, scattered rain in some areas in April and May, the period when crops need ample water to grow.

Luis Moreno, regional president of the union in the central region of Extremadura also said the situation had worsened since the data was collected.

"The drought is terrible," he said.

In its first estimate of this year's crop, the ministry said the wheat harvest was seen at 5.06 million tonnes, compared with 7.11 million last year.

It did not give a breakdown of soft and durum wheat.

The barley crop was forecast to fall 25 percent to 7.95 million tonnes. The number of hectares sown to each crop were roughly the same as last year, the data showed.

After the driest September to end-March stretch since records began in 1947, Spain, like its drought-hit neighbour Portugal, has asked the European Union for help dealing with the drought.

The Agriculture Minister has asked the EU for permission to import up to 8 million tonnes of cereals from EU intervention stores, in a letter seen by Reuters last week. Grain traders are sceptical about how much grain Brussels will allow Spain.

In the letter, the minister said she expected 50 percent of the crop to be lost. Because of the dry weather, water reserves stand at just 60 percent of capacity.

Farmers have started harvesting in the sun-scorched southern region of Andalusia but even in the most promising areas yields are less than a third of usual levels, a technician from farmers' union COAG in Seville said on Friday.

"Those are the best fields, that's not a good reference ... I think we'll lose 90 percent in Andalusia," Ramon Garcia said.