NATO’s new spending plan expected to be adopted this week will expose just how creative some of the alliance's members have been with their accounting.

That's because some reluctant military spenders in NATO have used an expansive definition when tallying their defence spending for the current 2% of GDP target, counting money spent on things like research and development, intelligence services or cyber defence.

The new proposed NATO 5% target under discussion, however, would be split into two categories: a new, broader set of "defence-related" items that could count for up to 1.5% of GDP, as well as a commitment to spend at least 3.5% of GDP on traditional defence items such as weapons, training and troop salaries.

“The bad news for allies, if that is adopted, would be that a lot of the things countries put in the 2% would then go into this new 1.5% security category, which would make it even harder to get to 2% strictly on military spending,” James Shea, who retired as NATO's deputy assistant security general in 2018, told Euractiv.