You are not permitted to download, save or email this image. Visit image gallery to purchase the image.
Alex Salmond, the leader of Scotland's devolved parliament, demanded an apology from Prime Minister David Cameron after not being told that an internal leak was found in 2012 at the Dounreay site in Scotland where a test reactor identical to those on Britain's nuclear submarine fleet is housed.
British Defence Secretary Philip Hammond said on Thursday that radiation had been discovered in cooling water around the reactor. He said the leak had not posed a safety risk and that nuclear regulators and Scottish environmental authorities and had been notified at the time.
Salmond's reaction shows the strained relations between the British and Scottish governments as campaigning before the referendum turns increasingly acrimonious. In recent weeks, nationalists have accused Britain of bullying over its refusal let Scotland share the sterling currency if it voted to split.
Salmond, who has promised voters a nuclear-weapons-free Scotland if they back independence, seized on the fact that the leak had not been disclosed sooner to the Scottish parliament.
"You must now offer an immediate explanation of why your government allowed this to happen, an apology for the disregard of established processes and a commitment that it will never happen again," Salmond said.
He criticised London for drawing a "veil of secrecy" over the incident, saying it had instructed the Scottish Environment Protection Agency (SEPA) not to disclose the leak.
A spokesman for the British Ministry of Defence said it had not ordered the information to be withheld from the Scottish government. SEPA said in a statement the Defence Ministry had asked that it use the information "on a strict need-to-know basis for security reasons".
The Scottish government also said Hammond's statement that there had been no measurable leak at the site was false, citing official data which showed a rise in the level of radioactive gases emitted at Dounreay between 2011 and 2012. SEPA data showed the level rose but remained less than half the annual limit.