The warming climate has created a "golden opportunity" for East Anglian farmers to grow more sunflowers, said seed merchants.

Grainseed, based at Eye, near Diss, has already seen "significant interest" in sunflowers to be sown in spring 2023.

The company says rising average temperatures are expanding the area capable of successfully growing the crop for oil and bird seed in the UK - previously reckoned to be the area south of a line between the Wash and the Bristol Channel.

Meanwhile global supplies have been hit by the war in Ukraine - which was the world's biggest sunflower oil exporter before the Russian invasion.

Seed specialist Angus Fox said increased demand could potentially support 40,000 hectares of sunflowers in the UK, but currently the area is only 300 hectares.

"With climate change and increasing temperatures, the geographic areas will undoubtedly expand for the crop in the UK," he said.

"We can produce good yields of good quality sunflower seed for the bird seed market. Of spring crops, sunflowers are an attractive crop for UK growers in terms of profitability.

"If you look at the top sunflower producers, Russia produces 16.5m tonnes and Ukraine 10m tonnes with Europe producing 9.44m tonnes.

"We have a golden opportunity, especially with increasing temperatures, to produce more sunflowers domestically in the future."

Grainseed general manager Neil Groom said demand for sunflower seed is already growing, particularly for the firm's best-selling variety named Bella, a high-yielding early crop which can be successfully cultivated as far north as the Wash.

"Bella is an early maturing variety and we have secured more seed for 2023 than we had last year," he said.

The company says sunflowers should be sown between the end of April and the middle of May, and are normally harvested from mid-September to October.