A top official in Kazakhstan has warned of the renewed threat of an invasion of locusts.

Bakhtyly Asainova, who's the agricultural head of the key grain-producing region of Pavlodar, told Reuters news agency that the region had received only half the pesticides needed to treat land infested with locust eggs.

She said nearly two million hectares of the worst affected land in Pavlodar needed to be treated in order to save this year's harvest.

Swarms of locusts hit Kazakhstan last year, and the problem has been steadily increasing since the collapse of the Soviet Union because of a drop in spending on pesticides.