Secretary of State Rex Tillerson said he was unable to make a scheduled April 5 gathering in Brussels. (Kevin Lamarque/Reuters)

The State Department and NATO said Tuesday that they were seeking an alternative date for Secretary of State Rex Tillerson’s first meeting with alliance foreign ministers, after he said he couldn’t make the scheduled April 5 gathering in Brussels.

But with little chance that ministers from 27 other member countries can change their schedules in the next two weeks to accommodate him, all sides scrambled to insist that Tillerson, whose president has regularly denigrated NATO, meant no disrespect.

“We will find a way to address this,” NATO Secretary General Jens Stoltenberg said in an interview. “The main thing is I’m absolutely confident about his absolute commitment to NATO.”

“Absolutely,” acting State Department spokesman Mark Toner said. “The United States remains 100 percent committed to NATO.” Past secretaries had also missed the twice-yearly meeting on occasion, he told reporters, citing one absence in 1999 and another in 2003.

Tillerson, dinged by Democratic lawmakers and the media as increasingly irrelevant after he missed several White House meetings with visiting foreign leaders, reportedly doesn’t want to miss President Trump’s meeting next month with Chinese President Xi Jinping in Florida. The date hasn’t yet been announced, but it is widely believed to be during the first week in April.

Questions raised about the NATO meeting were compounded by reports that Tillerson plans to travel to Moscow later next month. “If reporting is accurate, Donald Trump’s administration is making a grave error that will shake the confidence of America’s most important alliance and feed the concern that this administration [is] simply too cozy with [Russian President] Vladi­mir Putin,” Rep. Eliot L. Engel (N.Y.), the ranking Democrat on the House Foreign Affairs Committee, said in a statement.

Tillerson met last month with many of his NATO counterparts at an economic meeting in Germany. Nearly all of them, along with Stoltenberg, are in Washington this week to attend a broader counterterrorism meeting that the secretary is hosting. Vice President Pence and Defense Secretary Jim Mattis have visited alliance headquarters in Brussels.

But the extent of Trump’s commitment has been a recurring NATO nightmare since his election campaign, when he famously called the alliance “obsolete,” and said its best days were behind it. He would “certainly look at” getting rid of NATO, Trump said, since “it doesn’t really help us” and “we’re paying too much” for it.

More recently, Trump has tempered his remarks somewhat. At a news conference in Washington last week with German Chancellor Angela Merkel, he voiced “strong support for NATO,” even though “many nations owe vast sums of money . . . and it is very unfair to the United States.”

Stoltenberg moved early to bring Trump into the tent, during a call just days after the inauguration. With NATO’s new $1.2 billion Brussels headquarters scheduled to open later this year, he set the date for May 25 — when Trump was likely to be on his maiden presidential trip to Europe for a summit of the Group of Seven major industrialized nations — and invited Trump to attend along with other alliance leaders.

The building includes an “Article 5 Memorial” — a piece of the fallen World Trade Center towers, commemorating the only time NATO has invoked the mutual defense provision in its charter — and a Cold War memorial centered on a chunk of the Berlin Wall.

“It was clear we wanted very much a meeting with the new president,” Stoltenberg said, “to send an important message about transatlantic unity and about U.S. commitment to Europe.”

No one expects Trump to stop dunning NATO for more money, although his charge that many owe “vast sums” is misplaced. As Merkel’s government tersely pointed out following the news conference, member nations contribute capabilities, not cash, to their joint defense.

But the United States has for years pointed out that few members contribute their fair share. In 2014, all agreed they would bring their defense spending up to 2 percent of their gross domestic product within the next 10 years, a target that only five of 28 had met.

In the past two years, NATO has devoted more resources to counterterrorism, expanded a rapid-reaction force and, to meet a Russian buildup, is stationing 4,000 troops to its Baltic members. Decreases in defense budgets have stopped, and it increased overall last year by 3.8 percent.

“We’ve proven the last couple of years that NATO is able to adapt, to change,” Stoltenberg said. Improvements “are not only words, but also deeds.”

But he agrees with Trump that bigger defense budgets are a high priority, and he’s not altogether unhappy with the president’s continued focus on the issue.

As he travels to NATO capitals to meet with defense and finance ministers, Stoltenberg said, Trump’s “strong message makes my work easier.”