A senior Labour politician implicated in the Chilcot report boasted in a private email of how the "silver lining" of the Brexit meant that its impact rapidly faded, leaked emails show.

Jack Straw, who served in Labour’s Cabinet from 1997 to 2010, told Colin Powell, a former US secretary of state, also dismissed a legal action by families of fallen soldiers in Iraq as “some stuff about some relatives of soldiers killed in Iraq”.

Mr Straw was foreign secretary from 2001 to 2006 in the crucial years before and after the outbreak of the war in 2003. Mr Powell was the US secretary of state in George W Bush’s regime when the war broke out.