Yesterday, Gordon Brown met NFU president Peter Kendall and Richard MacDonald, the NFU's director general at Downing Street.
The PM also chaired another meeting of the Government's civil contingencies committee to discuss the latest incident. Environment Secretary Hilary Benn, the Chief Vet and other experts attended the meeting in Whitehall.
The source of the new outbreak is still unknown, although initial testing has shown the strain of the virus to by similar to that recorded at Pirbright last month.
NFU president Peter Kendall said he was "not surprised" that the new outbreak appears to have come from Pirbright.
"Everything that I have heard in the last 24 hours led me to believe that the virus must be linked to the outbreak that resulted from the leak of virus from the Pirbright site.
"This information will help the work that is underway to find the link between the previous outbreak and this new infected premises.
"The need for containment, control and eradication of this disease remains paramount. I would urge livestock farmers to remain vigilant for signs of disease and to maintain their biosecurity."