Why defence budgets are less secret than intelligence votes

Why is defence funding public when Parliament also has a secret-service vote?

Defence is a large declared departmental budget with NATO reporting obligations, whereas intelligence appropriations can remain less transparent.

The contrast follows from institutional scale as well as secrecy. Defence is a large department whose aggregate budget is publicly debated and reported, including declarations connected to NATO. Intelligence funding can instead remain concentrated in a less transparent secret-service vote. The frequency of the secret-service vote remains uncertain here, and no precise timetable is established.