Kenyan vegetable growers hit out at Britain's anti-food miles lobby this week at the Royal Agricultural Show in Warwickshire.

Kicking off a debate on whether food miles are fair miles, the Kenyan High Commission said it feared a consumer backlash against Kenyan flowers and vegetables in the wake of moves by Tesco and M&S to label airfreighted food with a special sticker.

"A debate is very healthy because it's important to tackle global warming," said high commissioner Joseph Muchemi. "But you can't zero in on airfreighting as the sole cause."

Most products airfreighted from Kenya were in the holds of passenger aircraft that would otherwise have flown with empty space, he claimed. "What we need is carbon footprinting," he said. "The retailers understand that. Talks with M&S and Tesco showed they don't think targeting airfreight is the fairest way to cut emissions."

Kenyan growers cited a Cranfield University study published earlier this year that indicated flowers grown in Dutch greenhouses had a bigger carbon footprint than those flown in from East Africa.

Kenyan imports accounted for just 0.1% of British carbon emissions, added the Africapractice consultancy, which helped stage the debate.

"They are a part of the carbon emissions issue, but not all of it by any means," said consultant Jo Crawshaw. "Local produce isn't always greener."

The High Commission used the debate to kick off a campaign to reclaim the moral high ground from opponents of airfreighting and highlight the social benefits of trade with Africa.

Fresh produce exports to the UK generated £100m a year for Kenya, supporting 135,000 people directly and hundreds of thousands more indirectly, said Crawshaw.