ANKARA, Turkey (AP) — NATO Secretary-General Mark Rutte on Monday demanded that the allies put forward “clear, concrete and credible plans” to reach the organization’s spending targets at its annual summit in Ankara.Rutte made the remarks in the Turkish capital come ahead of a two-day summit starting on Tuesday that comes at a time crucial time for the alliance with the United States scaling down its security role in Europe. Washington has been pressing allies to shoulder more of the spending burden.The 32 nations agreed last year to invest 5% of their gross domestic product on defense — 3.5% on their defense budgets and 1.5% on roads, bridges and ports so troops and equipment can move faster in times of conflict.Spain endorsed the goal but said that it could fulfill NATO’s security requirements without spending so much. Some countries are still struggling to meet the alliance’s old target of 2% of GDP.

Asked what would happen to allies that don’t have a clear plan, Rutte said: “If one or two of still have to be convinced, we have ways to do that.” He did not elaborate. U.S. Ambassador to NATO Matthew Whitaker suggested last week that the United States does have something in store for those who do not step up, but he declined to say what that might be.