Millions of locusts have devastated at least 2,000 hectares of crops in Sardinia, Italian farmers union Coldiretti said Monday, with experts calling the invasion the worst in six decades.

The most affected areas are Nuoro, Ottana and Orani in the middle of the Mediterranean island, with many areas blanketed by the insects, Coldiretti said in a statement.

The locust invasion is the worst in the area in 60 years, local entomologist Ignazio Floris told La Stampa daily.

The insect explosion is linked to a sharp rise in temperatures after a relatively cold May, with many of the young insects emerging from uncultivated land.

Cultivating land for crops discourages the insects laying their eggs in the autumn and prevents them reaching maturity in the summer warmth.

"The locusts emerge on uncultivated land but then they go to cultivated land to eat," said Coldiretti, adding that there is no current solution to the invasion.