The offspring of the 12 giant rabbits were supposed to help to feed starving North Koreans. Now doubts about their fate have brought an abrupt halt to one of the more unlikely hunger-alleviating projects.

Karl Szmolinsky sold the rabbits to Pyongyang so that they could be used to set up a breeding programme to boost meat production in the Hermit Kingdom.

However, amid concerns that they have been eaten by the country's leaders, Mr Szmolinsky will not be sending any more.

The 68-year-old breeder had been due to travel to North Korea after Easter to provide advice on setting up a rabbit farm. A North Korean official rang him last week to say that the trip had been cancelled. Mr Szmolinsky said he suspected that his rabbits, which grow to the size of dogs and can weigh over 10kg (22lb), were eaten at a birthday banquet for Kim Jong Il, the North Korean leader, although he emphasised that he had no evidence of this.

"It's an assumption, not an assertion," Mr Szmolinsky said. "But I don't think the animals are alive anymore, I think they've been eaten."

He added: "North Korea won't be getting any more rabbits from me, they don't even need to bother asking. I was looking forward to going on such a trip while I'm still fit enough."

The North Korean Embassy in Berlin denied that the rabbits were dead. A spokesman said that they were being used for a breeding programme, and had not been eaten. He added that no one at the embassy had contacted Mr Szmolinsky.

The reclusive communist country celebrated Kim Jong Il's 65th birthday on February 16 with crowds marching and singing in squares in the capital. The Government usually distributes extra food rations to mark the occasion but analysts doubt whether that happened this year because of food shortages and UN sanctions.

Mr Szmolinsky had attracted worldwide media coverage in January with his deal to sell North Korea some of the spectacularly large "German grey giants" he breeds at his home in Eberswalde, an eastern town near Berlin.

His rabbits can yield up to 7kg (15Ib) of meat each. It had been unclear, however, given their voracious appetite for carrots, potatoes and other top quality vegetables, how they could actually alleviate the food shortages in North Korea rather than actually adding to them.

He sold eight females and four males at a preferential rate of 80 euros (ยฃ54) each, a quarter of the usual price, and sent the rabbits in late 2006 in a consignment that included Robert, a friendly-looking monster who won a prize as Germany's largest rabbit.

Assuming he is dead, Robert lives on in his son, Robert II, safe in his hutch in Eberswalde.

In January Mr Szmolinsk said that the rabbits were being kept in a petting zoo in Pyongyang pending his arrival and that he would be prepared to deliver some more to North Korea.

Mr Szmolinsky does not have an especially emotional attachment to the 90 rabbits he breeds each year.

"The rabbits are meant to be eaten, they're like pigs, but these ones were exported for breeding purposes," he said. The 12 he sent could have created 60 news ones each year.

Meanwhile, Mr Szmolinsky, a prominent member of the Brandenburg Rabbit Breeders' Association, said he has been in talks with potential rabbit buyers in several countries including Russia, which wants 400, the United States and Cameroon.

"China is sending a delegation to inspect my animals in June or July and may ask me to go to Shanghai," he added.