Roger and Meiriona Bateman. Pic: Llanelli Star.

Pensioners Roger and Meiriona Bateman were sent the letter by British Gas that stated unless they made an immediate payment their supply would be disconnected.

The couple were even given a telephone number to call if they had difficulty paying the demand.

British Gas said it was an automatic letter that was sent out by mistake and has offered them �20 as a gesture of goodwill.

This was a standard automatic letter and if someone had realised, it would not have been sent British Gas

Mr Bateman said: "It's intimidating wording. We are just going to ignore the bill and wait for them to come and cut us off.

"I'd have thought someone was trying to wind me up if it wasn't an official document.

"When my wife opened the bill she couldn't stop laughing. I've shown it to friends and they couldn't believe it."

The 69-year-old said he had paid their last bill, sent in December, in full.

A spokeswoman for British Gas has apologised for the mistake.

Donna Davies said: "We have apologised and obviously we will not be cutting them off.

"This was a standard automatic letter and if someone had realised, it would not have been sent.