European Union leaders have committed to raising defence spending to NATO's guideline of two percent of the GDP.
They have agreed that in the past as well but never achieved it.
Only the United States spends significantly more - $650bn last year.
President-elect Donald Trump has questioned whether the US should be prepared to protect allies who do not meet their share of NATO funding.
Thursday's decision by EU leaders is a reflection of the uncertainty that hangs over European military affairs.
Many countries are wary of both an increasingly expansionist Russia and of the uncertainty surrounding the incoming US administration.
Presenter: Sami Zeidan
Alex Kokcharov - Lead Russia analyst at IHS Markit Country Risk
Marko Mihkelson - Estonian member of parliament and head of the Estonian delegation to the NATO Parliamentary Assembly
Mark Jacobson - Former adviser to US Secretary of Defence Ash Carter
Source: Al Jazeera News