Speak less, stop the trash talk, do not give ammunition to Russia, be serious and consistent are the messages from European and Nato leaders to Donald Trump.

The constantly changing messages, often couched as derogatory taunts from the US president is alarming European allies who fear mixed signals from Washington risk feeding Putin’s narrative as Nato once again tries to weather a storm triggered by Trump.

“I believe that organisations and alliances like NATO are defined by what is left unsaid – by the trust that underpins them,” French President Emmanuel Macron told reporters on Thursday from South Korea, cautioning that repeatedly casting doubt on commitments “strips [the alliance] of its substance”.

“We need to be serious. When we want to be serious, we don’t say the opposite of what we said the day before every single day. And perhaps we shouldn’t speak every day,” he added.

The remarks came after Trump, voicing frustration with European allies over what he sees as insufficient support for his war in Iran, suggested the US could reconsider its role in NATO.

Asked by Reuters on Wednesday whether he was considering pulling out of the military alliance, he replied: “Oh, absolutely without question. Wouldn’t you do that if you were me?”

His comments have unsettled allies already grappling with Russia’s war in Ukraine, raising fears that public ambiguity over Article 5 commitments could weaken deterrence and embolden Vladimir Putin, the Russian president, at a critical moment for European security.

Donald Tusk, the Polish prime minister, delivered a stark warning on Thursday, saying that talk of weakening the alliance, easing pressure on Russia and reducing support for Ukraine “all looks like Putin’s dream plan.”

However, Alexander Stubb – the president of Finland who was once described as a Trump whisperer – struck a more conciliatory tone on Wednesday evening after speaking with the US leader, saying the two had held a “constructive discussion” and stressing that “problems are there to be solved, pragmatically.”

Looking beyond the ‘trash talking’

But at the alliance’s Brussels HQ, officials fear with every new day of Trump “trash talking” the alliance down, the public’s faith in the US’s role as NATO’s security guarantor is weakened.

“Everyone is trying to look beyond the flow of trash talking and the fundamentals are actually good,” a senior NATO diplomat told Euractiv.

Camille Grand, a former assistant secretary general for defence investment at NATO, told Euractiv that capitals are probably split between dismissing Trump’s rhetoric as familiar, citing similar belligerent comments over defence spending and Greenland, and worrying about its cumulative impact.

Some therefore probably think that “Trump is Trump”, Grand, who is now secretary general for the European Aerospace, Security and Defence Industries Association (ASD), said, arguing that “he’s been saying things like this since 2016” and yet “it never really crystalised into a deliberate moment of leaving”.

But another way some might be looking at it “is that things pile on, one mini crisis after another, that becomes a political problem”.

What it does demonstrate though is that “the strategic views of the Europeans and the Americans are not entirely aligned, to use an understatement,” Grand said. He added that in peacetime it would matter less, but with wars in Europe and the Middle East and a broader geopolitical crisis, Trump was instead signaling a willingness to act on his own terms rather than regroup with allies.

It makes advancing much-needed conversations within NATO about capability building, ramping up defence production, and burden-shifting difficult and could also impact the next leaders’ summit to be held in Ankara in July, Grand said, stressing though that much can happen in three months, including a de-escalation from Trump.

“Before Iran, I was told by many former NATO colleagues, that industry would be at the heart of the conversation in Ankara, that we would be super focused on how to deliver the capabilities that are needed,” he said.

Max Becker, a security and defence policy fellow at the German Council on Foreign Relations, similarly stressed that it gets the alliance “nowhere to hold a new debate every two months on whether NATO will fall apart as a result of the SU President’s latest remarks”.

“A priority for Europe should be to further Europeanise NATO,” he told Euractiv, and to focus on strengthening much-needed capabilities.

Charles Cohen, Kjeld Neubert, and Bruno Waterfield also contributed to reporting.

(bw, cs)