The first signs of a revolt are starting to appear over the introduction of compulsory identification for all sheep. A group of about 100 North Wales farmers with 120,000 sheep between them have vowed to boycott the EU regulations until such time as "workable equipment" becomes available.

Their move, supported by both farming unions, is the first sign that frustration is starting to boil over at EU plans which will virtually force an electronic ID system on the country from January.

Individual recording is seen as the Commission's final response to the chaos of the 2001 foot-and-mouth epidemic when the disease was allowed to rampage out of control because animal movement records were so inadequate.

But British farmers say it will unfairly hit them as owners of the 30-million largest national flock in the Community.

Trials have already been carried out at various places around the country, including in the South West. But a Welsh farmer, who has been using EID technology on his farm for the last 12 months, has reported that out of 1,200 sheep some 200 had lost their tags – making the system, unworkable.

Farmer Gareth Wyn Jones, who is secretary of his local graziers group, said: "We decided there and then that we will not be going down the road of EID until EU officials can come up with a workable system.

"These European pen-pushers really want to think before they pass these ridiculous regulations."

Meanwhile, attitudes appear to be hardening over the introduction of the regime following the week-long visit by EU officials.

They saw the electronic tag-reading system being demonstrated at a number of locations, including Sedgemoor Auction Centre in Somerset – but appeared unmoved by farmers' warnings that the system would be unworkable on hills where flocks several thousand strong are kept.

National Sheep Association chief executive Peter Morris said their view appeared to be that there was no way back from the regulation being enforced.

"All we have had shoved down our throats as a sheep industry is that this is all about coping better with disease outbreaks, yet no one can tell the sheep farmers who will have to live with it how it will make a difference."

And NFU livestock board chairman Alistair Mackintosh said: "They seem reluctant and unable to grasp the enormity of the impact this regulation will have on sheep farmers. As we have repeatedly said, this regulation makes no sense and has the potential to dramatically affect the sheep industry across the EU.

"The additional costs involved, coupled with the recording requirements, will force many producers out of business while having absolutely no cost benefit, and we will continue to work with other member states to get the proposed regulation overturned.

Mr Mackintosh urged any sheep farmers who had not yet done so to complete the survey issued by the NFU in conjunction with NFU Cymru and NFU Scotland about how the proposed introduction of electronic identification and individual recording will influence their intentions to continue keeping sheep.