The Pentagon's top policy official told NATO ambassadors this week that the United States is not seeking unlimited authority over European bases, but does want firmer guarantees that it can use them.

Elbridge Colby, the U.S. under secretary of war for policy, met the North Atlantic Council at alliance headquarters in Brussels on Thursday to brief allies on the review of American force posture in Europe, NATO said in a statement. About 80,000 U.S. troops are stationed on the continent, and European capitals have spent the summer waiting to learn whether the review will cut that number further.

Speaking to reporters afterward, Colby said Washington was not looking for a complete carte blanche in every context but needed predictability, and he pointed to the recent war with Iran as a case where reliable access had not always been there, Air and Space Forces Magazine reported. Some European officials pushed back. They said it was unrealistic to expect quick agreement on access for American warplanes in a war they had not been consulted about and that did not involve the alliance.

The criteria governing the review were set out in a terms of reference document shared with allies. They cover what European states are doing to meet higher defense spending targets, how they plan to fill the gaps as Washington shifts resources away from Europe, and their willingness to support American power projection beyond NATO through space, cyber and intelligence assets as well as base access, Reuters reported.

Colby's visit followed meetings at U.S. European Command in Stuttgart and at Supreme Headquarters Allied Powers Europe in Mons. He met NATO Secretary General Mark Rutte earlier the same day.

The anxiety in Brussels has a recent history. The Pentagon has already withdrawn two Army combat brigades from Europe as it presses allies to take the lead on conventional defense. Congress answered by writing a floor of 76,000 military personnel in Europe into the 2026 defense authorization, permitting further reductions only after the Pentagon shows it has consulted allies, Foreign Policy reported.

European officials have countered with numbers of their own. Rutte has said European allies and Canada generated an additional $258 billion in defense investment across 2025 and 2026.

No final decision on troop levels has been announced.