US Defense Secretary Pete Hegseth sharply rebuked several NATO partners while launching a six-month evaluation of American military deployments on the continent.

Addressing fellow defense ministers in Brussels, he warned that certain nations would fall short while others would meet expectations fully, pointing to those he accused of relying too heavily on US support.

Hegseth also faulted alliance members that restricted assistance to American units during the conflict with Iran.

The review follows Washington's decision to lower its contributions to NATO's high-readiness structure, known as the NATO Force Model.

Hegseth described the effort as NATO 3.0 and said its goal is to push the alliance swiftly toward greater European responsibility for continental security.

Washington is pressing allies to increase defense outlays and wants clearer road maps showing how they will hit the 5 percent of GDP target, broken down as 3.5 percent for core military needs and 1.5 percent for supporting infrastructure.

NATO Secretary-General Mark Rutte noted that spending rose by 90 billion euros last year, nearly a 20 percent jump, and said European members are already compensating for reduced US commitments.

Exact details of the planned US reductions remain undisclosed, though air and naval assets are expected to be affected.

Hegseth stated that future US payments to the alliance would depend on whether partners meet spending goals, adding that shortfalls would lead to lower American contributions.

He observed that some of NATO's wealthiest members continue to discuss international rules while appearing reluctant to increase their own defense budgets.

The secretary did not name specific countries.

A senior NATO official acknowledged that not all withdrawn US capabilities can be fully replaced, yet Rutte stressed that replacement work is already under way and that the adjustments begin immediately.

The NATO Force Model comprises units the Supreme Allied Commander Europe can rely on at short notice, the official noted.

In May the United States said it would remove 5,000 troops from Germany following tensions between President Donald Trump and German Chancellor Friedrich Merz over Iran policy.

That same month Poland was notified of a 4,000-troop withdrawal, a plan later reversed when Trump pledged to send 5,000 instead.

Poland currently hosts up to 10,000 US personnel on rotation, and Defense Minister Władysław Kosiniak-Kamysz said Thursday that Washington is considering Warsaw's offer of a permanent base, with a final call resting on agreement specifics.

Trump earlier threatened to end all trade with Spain after Madrid barred use of its air bases for operations against Iran; the United States maintains Naval Station Rota and Morón Air Base on Spanish soil.

Rutte said Wednesday he expects members to outline how they will fulfill the 5 percent commitment ahead of the Ankara summit in July.

He added that allies will present clear plans to reach the target by 2035, ideally sooner, and noted that several nations are already advancing toward that objective.