Some things may go without saying, but Belgium's food agency issued a public health warning as the festive season wrapped up: don't eat your Christmas tree.

The unusual message came after the city of Ghent, an environmentalist stronghold in the country's northern Flanders region, raised eyebrows by posting tips for recycling the conifers on the dinner table.

Pointing with enthusiasm to examples from Scandinavia, the town website suggested needles could be stripped, blanched and dried - for use in making flavoured butter, for instance.

Asked what they thought of the idea, the reply from Belgium's federal agency for food chain security, AFSCA, was a resounding "No".

"Christmas trees are not destined to enter the food chain," it said in a statement.