NATO members are set to agree to a goal to increase their defense spending level to 5% of their GDP as a means to address a long-held grievance by President Donald Trump.

Secretary of State Marco Rubio said Thursday all NATO nations "will have agreed on a goal" of reaching 5% in defense spending over the next decade by time the military alliance has held its summit next month.

US Secretary of State Marco Rubio said on Thursday that all NATO members will have agreed on a goal of spending the equivalent to 5% of GDP on defence over the next decade by the 2025 NATO Summit in June.