An ancient variety of grape no larger than a petit pois has been introduced by Marks & Spencer.

The Black Corinth, first grown in Greece around 72AD, is one of the world's oldest varieties. It is also among the smallest, with grapes typically 8mm to 10mm in length less than half a standard grape.

The ultra-sweet grapes (rsp: £2 for 300g) are best eaten 'Grecian' style, M&S grape specialist Stuart Henderson claimed.

"You place the miniature vine in your mouth and remove the grapes with your your lips," he said.