U.S. 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 defense over the next decade by the 2025 NATO Summit in June.

Secretary of State Marco Rubio told NATO allies that much more defense spending is needed to reinforce the 32-nation security pact.

Slovenia and several NATO member states are seeking ways to expand the definition of defense spending as they attempt to meet US calls to allocate more funds on security, the nation’s prime minister said.