Defra has moved to clarify its sourcing record on British food after Caroline Spelman mistakenly suggested that less than a fifth of the food the department bought came from the UK.

The environment secretary yesterday told the House of Commons her department sourced just 18% of its food and drink domestically. However, the department today said the true figure was 30%.

“We can’t insist that our caterers only use British produce because it would be illegal under EU trade rules, and in any case not all foods are grown in the UK,” a Defra spokesman said.

“But wherever possible we want to see food that adheres to high welfare standards. Defra’s caterers already source 100% of the milk, pork, and beef that we serve from the UK and we expect to see more quality, high-welfare produce in our canteens.”

Defra added that the 30% figure related to the volume – rather than value – of the food it procured.

Spelman made her original comments during parliamentary questions yesterday. She said World Trade Organisation rules meant Whitehall could not mandate that the produce it bought be British but could require that all produce adhered to British standards.

“We adhere to those rules, and we actively promote government buying standards involving all departments sourcing food that is produced to British standards in order to promote those standards,” she said.

Defra spearheaded the introduction of new government buying standards for food last year, which include requirements on sourcing a certain proportion of foods to higher environmental and welfare standards. However, in October, food and farming minister Jim Paice was forced to concede that Defra had failed to meet some of its own standards, before vowing to take action to improve the department’s performance.