CAMPAIGNERS have denounced the UK Government’s decision to play “transatlantic nuclear ping-pong” by agreeing a deal to transport 700 kilograms of weapons-grade uranium fuel from Dounreay in Caithness to the US.

The SNP’s Paul Monaghan, the local MP, said he too was deeply concerned by the development and is to demand assurances from David Cameron about the safety of the transportation, which he believes will involve up to nine flights from Wick airport using huge American c-130 Galaxy aircraft.

“Wick airport is not built for that kind of aircraft. I’m very concerned about the prospect of the planes flying over the town,” declared the backbencher.

Mr Monaghan stressed that the highly-enriched uranium fuel, which he said had originated from the former soviet state of Georgia, could only be used for nuclear weapons.

Claiming the Prime Minister had “obfuscated” in his replies when asked previously about the planned shipment of nuclear fuel from Dounreay to the US, the Nationalist MP said the safety of local people was his “paramount concern” and that the UK Government, through its lack of clarity, was “abrogating its responsibility to the people of Scotland”.

Mr Cameron is due formally to announce the deal when he attends an international nuclear security summit in Washington DC tomorrow. It will involve the largest ever shipment of radioactive material from the UK to America, which in turn will send a different form of the nuclear element to Euratom, the European atomic agency, for conversion in France into medical isotopes to be used in European hospitals for the diagnosis and treatment of cancer.

A UK Government source said: "It's a win-win; we get rid of waste and we get back something that will help us to fight cancer."

But Richard Dixon, director of Friends of the Earth Scotland, said: “Only the nuclear industry could think it was a good idea to risk playing ping pong with large quantities of one of the most dangerous materials on the planet across the Atlantic.

“Europe is littered with plenty of highly radioactive waste from both reactors and weapons, there cannot possibly be a need to be importing any more from the US, nor for us to be sending ours to them.”

He added: “Nuclear waste should be dealt with as close to where it is produced as possible rather than risking transporting it in ships or planes. This waste will remain dangerous for tens of thousands of years. The consequences of an accident during transit would be horrific."

John Finnie, justice spokesman for the Scottish Greens, dismissed the UK Government’s attempt to present the proposal to send dangerous nuclear waste across the Atlantic as helping in the fight against cancer as “at best misleading and at worst cynical”.

He added: “Moving such a large amount of toxic waste shows callous disregard for the safety of people in the Highlands. There must be better ways to fight cancer than sending dangerous uranium on an 11,000 kilometre round trip."

Whitehall has, for security reasons, not confirmed the details of the transportation or the timescale.

Last year, the Sunday Herald broke the story about a “secret plan” to ship nuclear material from Dounreay to America.

The report said the plan was for nearly five kilograms of enriched uranium to be transported by sea from Caithness to the US Government's nuclear complex at Savannah River in South Carolina.

The material was said to have come from a research institute in Mtskheta, some six miles from the Georgian capital, Tbilisi, in a secretive US operation codenamed Auburn Endeavour in April 1998. Washington was said to have been worried at the time that it could have fallen into the hands of Chechen gangs or Iran.

However, the proposed UK Government plan is to ship not five kilograms but 700kg or more than 110 stones of the nuclear material.

At the time of “secret plan” report one anti-nuclear campaigner warned the proposed shipment sent an “open invitation to terrorists keen to get their hands on this prime terrorist material".

The summit in Washington will discuss how to prevent terrorists getting hold of radioactive material with the UK set to play a leading role in protecting nuclear facilities from cyber attack.

Next year, the UK and US will take part in a joint exercise to prepare for any online attack against nuclear power plants and waste storage facilities.

Mr Cameron is to offer British expertise to other countries to safeguard their own civil nuclear installations amid fears jihadists from so-called Islamic State could attempt to create a dirty bomb.

The summit, hosted by Barack Obama, will see heads of government consider their response to the nightmare scenario.

The attacks in Brussels have raised fresh concerns about the prospect of nuclear terrorism.

Belgian media reported that two of the suicide bombers in the attacks, brothers Ibrahim and Khalid El Bakraoui, had video footage of the home of a senior official at a Flanders nuclear waste facility.

A UK Government source said there was no "credible evidence" that terrorists were targeting British facilities.

But the cyber attack exercise with the US would ensure that both governments and their civil nuclear industries were prepared and could address any potential weaknesses.

The source explained: "You saw just last week in Belgium concerns that were raised around the security of civil nuclear sites and, therefore, in the world in which we currently live, it's the right thing to do."

Alongside the US-UK exercise, Mr Cameron will use the summit to offer British expertise on cyber security.

Countries including Japan, Turkey, South Korea and Argentina have all expressed an interest in learning from British "experience and expertise", with other nations expected to follow, the source said.

The UK will also commit £10 million this year to improve security standards around nuclear plants and waste facilities.

"There is a role we can play along with the US in terms of improving these standards," the source said.

The gathering will be the fourth and final nuclear security summit, following on from the previous meeting at The Hague in 2014.

The summits were the personal initiative of Mr Obama and the final meeting will see world leaders take part in a "scenario-based session" focusing on the "threat from nuclear terrorism".

The Whitehall source said the UK wanted to support the US to make sure there was a "lasting legacy" with the International Atomic Energy Agency taking forward the work on nuclear security.

In the margins of the summit representatives from the world powers involved in the talks on Iran's nuclear programme - the UK, US, Germany, France, China and Russia - will also discuss progress made on the agenda.