BRUSSELS >> For decades, America’s chief diplomat has been greeted in Europe’s heart with broad smiles and open arms.

That tradition appeared to have been suspended today.

Secretary of State Rex W. Tillerson’s reception in Brussels was distinctly chilly, as disappointment among European diplomats in President Donald Trump’s nationalistic tone and insulting messages on Twitter built into quiet fury on the eve of an expected announcement that the United States would recognize Jerusalem as the capital of Israel. Such a move could infuriate the Palestinians, who want East Jerusalem to be their capital in a future Palestinian state.

In a brief public appearance beside Tillerson, Federica Mogherini, the European Union’s top diplomat, gave the kind of stone-cold statement of facts that she would normally provide standing beside her Russian counterpart, not the U.S. one.

She made clear that the European Union saw the Trump administration’s possible announcement on Jerusalem as a threat to peace in the Middle East.

“We believe that any action that would undermine these efforts must absolutely be avoided,” she said. “A way must be found through negotiations to resolve the status of Jerusalem as a future capital of both states.”

Mogherini also warned the United States not to walk away from the Iran nuclear deal, something Trump has said he may do.

“The continued implementation of the Iran nuclear deal is a key strategic priority for European security but also for regional and global security,” she said.

Tillerson’s spokesman, R.C. Hammond, acknowledged the less-than-warm reception.

“Allies have been very frank today in sharing some of their views,” Hammond said.

Mogherini’s remarks came just hours after Foreign Minister Sigmar Gabriel of Germany declared at a foreign policy conference in Berlin that relations with the United States “will never be the same” and said that the Trump administration increasingly viewed Europe as a “competitor or economic rival” rather than an ally.

On Monday, President Emmanuel Macron of France warned Trump in a phone call that recognizing Jerusalem as the capital of Israel was a bad idea, joining leaders from Jordan, Egypt, Turkey and the Arab League in speaking out publicly against the move.

Trump’s nationalistic rhetoric and frequent complaints about what he sees as European freeloading on U.S. military spending has long grated on European leaders, but in recent weeks their annoyance has turned to anger.

When Tillerson and Mogherini gave public statements, Mogherini never smiled and she refused to answer questions.

Into this growing rift the Trump administration sent a chief diplomat who could be pushed out within weeks and has little of the president’s confidence, according to senior administration officials.

For his part, Tillerson stood beside Mogherini and offered innocuous comments in which he reaffirmed “the important role that the European alliance plays in our shared security objectives.”

Tillerson spoke at far greater length in a morning visit to the U.S. Embassy in Brussels but spent most of his time describing his departmental reorganization effort, not addressing the growing diplomatic challenges his employees face in Europe and elsewhere.

He admitted that the Trump administration had yet to notch a single major diplomatic victory.

“While we don’t have any wins on the board yet, I can tell you we’re in much better position to advance America’s interests around the world than we were 10 months ago,” Tillerson said.

He promised to announce his reorganization plans within weeks and grew animated when describing the process. Tillerson made the remarks at the ambassadorial residence, which is not presently occupied. The administration has yet to nominate ambassadors to both Belgium and the European Union.

From Brussels, Tillerson heads to Vienna, where three ambassadorial jobs — to Austria and two European bodies — also remain unfilled. Dozens of top jobs in the department are empty.

“We’re still awaiting a lot of nominees to clear the processes and be confirmed,” he told the gathering. “I get a little criticism for that from time to time.”

Tillerson’s own delays in identifying leaders also has been a big obstacle. Now that he may leave within weeks, the White House vetting process for his choices has slowed to a crawl.