NATO said it was working to understand details of the plan to draw down about 5,000 troops, which coincides with a feud between the president and the German chancellor.

The pageantry began Monday amid heightened security concerns and a growing rift over the Iran war. The U.K. hopes the president’s love of pomp and the king’s “poker face” can help heal their alliance.

The announcement came as talks set to take place between U.S. and Iranian delegations in Pakistan were postponed amid uncertainty about the broad strokes of a deal.

Iran has not confirmed Trump’s claim. Giving up its highly enriched uranium would be a major step toward an agreement.

The president, long a NATO skeptic, has been especially angry at alliance members in recent weeks for declining to take part in the U.S.-Israeli war on Iran.