Although the risk is difficult to quantify, senior management at the plant are confident the company is as prepared as it can be. A spokesman said only “essential visitors” were being welcomed on site.

“The basic precautions we have at the factory now are the same as those that have been in place for a number of months now,” he remarked.

“We are limiting all non-essential visitors and a range of security measures are in place.

“We are being very vigilant and have ensured all the precautionary measures we can realistically take are being taken.”

Meanwhile, senior figures within Perth and Kinross Council, including officials from the emergency planning department, were meeting today to discuss the Fife discovery and its implications.