No 10 says that it will not release the e-mails because they relate to the “formulation of government policy”, which could suggest they reflect the arguments going on about the legal flaws in the case for war.

Senior government sources suspect that the e-mails contain a summary of the arguments that No 10 was privately making to Goldsmith that, contrary to his original advice, war was justified because Saddam Hussein was in breach of United Nations resolutions.

A senior source at the Department for Constitutional Affairs, which Falconer heads, said colleagues had been been “s***ing” themselves that the Morgan e-mails would be released after No 10 went against precedent and released Goldsmith’s full legal advice during the election.