A recent US Congressional Hearing tried to establish the answer to the question:
“If a sophisticated cyber-attack occurred against the United States financial systems, who would coordinate the response?”
You might think that this straightforward question would get a simple answer, but apparently the answer it produced was:
“We’re in the process to building out a national cyber incident response plan, and that plan would more clearly define roles and responsibilities of the different departments and agencies.”
Pressed again by the Congressmen, the witnesses acknowledged:
“I think that’s one of the challenges that needs to be addressed: Who is actually in charge? With the White House cybersecurity coordinator in place now, what is his role relative to at DHS? I think that is certainly a valid challenge that still remains to be addressed.”
However, if it is confused in the United States, I would be surprised if there was any clarity if the same question was asked in the UK.
I might table a Parliamentary Question and see.