Some 336,000 hectares of forest and scrubland have been burned, according to a provisional estimate, the forest service said in a statement.

This was the largest area of Portugal hit by forest fires since 1980, when statistics were first kept, a government official explained.

Forests cover some 3.3 million hectares in Portugal.

The previous record was in 1991 when more than 180,000 hectares were burned, the official told AFP.

The latest estimate, which does not include damaged farmland, still requires final confirmation, the forestry statement said.

Some 20,000 to 30,000 hectares of farmland have been swept by fire, a forestry official told a radio station.

Portugal has been the hardest hit by the forest fires that flared across Europe this summer, with blazes decimating vast stretches of forestland and brush and claiming 18 lives.

Police have arrested 73 people suspected of deliberately sparking wildfires.

Portuguese authorities had earlier estimated the damage to forestland at 215,000 hectares, an area the size of Luxembourg. But this figure did not include the southern Algarve region.

The fires have dealt a heavy blow to Portugal's forestry industry, which accounts for 11 percent of the nation's exports.

The European Union's Executive Commission is expected to grant Portugal disaster relief aid to help cope with the damage from the blazes, which the government has so far estimated at one billion euros (1.1 billion dollars).

A definitive calculation of the extent of the damage will take some time because fires are still burning, officials say.

"Even though the main wave of fires is over fires continue to rage," said a forest service official. "Statistics are continually being revised upwards."

TERRA.WIRE