The National Maritime Museum, which is due to reopen in two weeks after a pounds 20m refit, had been hoping to display the Greenpeace survival pod as the centrepiece of its exhibition on the future of the sea. But after the lobby group used it for one last campaign, it was impounded by the Norwegian authorities, who are refusing to give it back.
Not only will they not return it, but when David Spence, head of display and exhibitions at the museum, went to Trondheim last week, he was told in no uncertain terms that if he wanted his pod he would have to buy it back at public auction.
"This pod is one of the key exhibits and at the moment all visitors will be able to see is a gaping hole," he said.
Last summer, Greenpeace offered the pod, which is equipped with satellite communications and survival gear and was used for its occupation of Rockall in the North Atlantic, to the museum as an exhibit.
But there was one proviso: they wanted to use it once more. The museum was only too happy to agree and the campaigners duly lowered themselves into the pod, which can sustain three people, in admittedly cramped conditions, for several months. It was then lashed to a Statoil rig in protest against the opening up of new oilfields north-west of Britain.
It was not long before the Norwegian police arrived and, after "a bit of a battle", the pod, its occupants and their boats were taken into custody.
There the problems began. The court case was repeatedly delayed and the authorities refused to release the pod, the only one of its kind. "We engaged lawyers to plead on our behalf, the Foreign Office wrote a letter, we told them the Queen of England was coming to the opening and what would she think. They have remained unmoved," said Mr Spence.
Indeed Commissioner Lilleberg, the chief of police of Kristiansund, where the pod is being guarded, said yesterday: "I am appointed by the King of Norway, who is related to your Queen, to do my job properly and that means I have to keep this pod until the court case. If the court says the Norwegian state can keep the pod then it will be put up for auction."
Mr Spence said he couldn't help but feel that the Commissioner was being deliberately obstructive. "This display is about both sides of the argument and we have included a North Sea oil rig drill bit. We think the reason is the long history between the Norwegians and Greenpeace over whaling and we are stuck in the middle."
The pod, which was specially built for Greenpeace from the same material used to make bulletproof vests, cost around pounds 30,000 to construct.
"We have considered using a replica pod which has been used for promotional work, but museums are about real things."
In the meantime, Her Majesty is almost certain to preside over a somewhat empty opening ceremony. Unless, of course, she could be persuaded to have a quiet word with her cousin, King Harald.
r The Green Party's European election campaign is to be bankrolled by the billionaire Goldsmith family. Teddy Goldsmith, brother of the late Sir James, has pledged to help to finance the Greens so they can gain their first Euro MPs.