US President Trump has continued his tirade against German Chancellor Friedrich Merz, who heads the government one of America’s most important allies, telling him to “spend more time ending the war in Russia/Ukraine,” rather than commenting on the Iran war.

“The Chancellor of Germany should spend more time on ending the war with Russia/Ukraine (Where he has been totally ineffective!), and fixing his broken Country, especially Immigration and Energy, and less time on interfering with those that are getting rid of the Iran Nuclear threat, thereby making the World, including Germany, a safer place!” Trump wrote in a post on his Truth Social platform.

It follows on from a late night post on Wednesday where Trump threatened a significant reduction in the number of US troops stationed in German.

“The United States is studying and reviewing the possible reduction of Troops in Germany, with a determination to be made over the next short period of time,” Trump wrote.

Trump’s barrage of criticism comes in response to Merz’s comments on Monday that the US was being “humiliated” by the Iranian leadership. Merz said Tehran had out skilled the White House team of negotiators.

“An entire nation is being humiliated by the Iranian leadership, especially by these so-called Revolutionary Guards,” Merz said.

“The Iranians are clearly stronger than expected and the Americans clearly have no truly convincing strategy in the negotiations either,” he told students in Marsberg.

Merz also slammed Washington for having what he perceived as an ill-conceived strategy for starting and ending the war.

On Thursday afternoon, at a visit to troops at a military area in Munster, Merz reportedly didn’t directly address Trump’s threats regarding the troop drawdown, but referenced instead the endurance of the transatlantic partnership.

“On all these [world] issues, we maintain close and trusting contact with our partners, including, and especially, those in Washington,” he said. “We do this in the shared transatlantic interest. We do so with mutual respect and a fair sharing of the burden.”

Trump’s announcement that he is considering reducing the number of troops in Europe is not new, but NATO experts say the frequent pronouncements have eroded the transatlantic alliance irretrievably.

The time has come to think of “Europe without the US,” former NATO Policy Director Fabrice Pothier told EU News.

Pothier said Europe is going through a “boiling frog moment” when it comes to relations with Washington, where “the situation gets worse every year,” but European states are then reassured by the US that “it’s still a good ally,” he said.

The boiling frog refers to a person’s refusal to acknowledge existing threats, through the metaphor of a frog in a pot of lukewarm water which slowly starts boiling, endangering it gradually.

He said Europe needs to immediately scale up its collective defence in order to stand alone in the face of future threats to the continent.

“There has to be an assumption that the US will not be in the Article 5 mindset if and when it’s presented with scenarios,” where Europe needs its support, he said.

Article 5 of the NATO charter is the cornerstone of the alliance which states “an attack on one is an attack on all.”

There is now a “tiredness among European leaders for dealing with Trump’s bully tactics,” Poitier told EU News.

In recent months, Trump has revoked sanctions on Russian oil, a key pillar of the Western response to Russia’s war in Ukraine. He has also threatened to annexe Greenland, a semi-autonomous territory of Denmark.

He frequently delivers searing verbal assaults against NATO allies for not joining him in the Iran war, despite not having consulted them about it before it started.

Last week a leaked email from the Pentagon floated the idea of punishing Spain and the UK for their leaders’ criticism of the war.

“The US has put has itself in stupid situation which has massive global consequences,” and “leaders are now less concerned about criticising this,” Pothier said.

“This is not the first time he talks about reducing US forces in Germany, so we have to realise there is something to it.”