European states should be prepared in case the US will not come to their aid, the French president has warned.

France will discuss the possibility of using its nuclear arsenal to protect its allies in Europe, President Emmanuel Macron has said. He made his statement as NATO members are growing increasingly worried that the United States under President Donald Trump would not come to their defense. 

Last month, Germany's chancellor-designate, Friedrich Merz, suggested that Britain and France could extend their nuclear protection to Germany, given the tensions between Russia and NATO over Ukraine. Such offers had "always remained unanswered," he said. 

In a speech on Wednesday evening, Macron said that he was open to extending his country's nuclear umbrella. "In response to the historic appeal by the future German chancellor, I have decided to open a strategic debate on protecting our allies on the European continent through a nuclear deterrent," he said, according to RFI.

The president said that people in France were "legitimately worried" about the "new era" under Trump. "I want to believe that the United States will stay by our side, but we have to be prepared for that not to be the case," he said.

Trump, who was elected on the slogan "America first," has demanded that European allies contribute more to their own defense. He further broke with many NATO countries by refusing to unconditionally back Ukraine against Russia and instead opted to launch direct talks with Moscow. 

Trump's drastic departure from the policies of his predecessor, former President Joe Biden, prompted America's allies in Europe to question whether they could rely on Washington for their defense. "Europe faces a clear and present danger on a scale that none of us has seen in our adult lifetime," European Commission President Ursula von der Leyen wrote in a letter to the bloc's member states on Tuesday.

The US president has stressed that it was his priority to broker a ceasefire between Moscow and Kiev and to prevent the conflict from spiraling into a full-scale war between nuclear powers. During a heated exchange in the Oval Office on Friday, Trump accused Ukrainian leader Vladimir Zelensky of "gambling with World War Three."

Russia has accused NATO of saber-rattling and stated that the deliveries of Western weapons to Ukraine are raising the risks of dangerous escalation. "We believe that nuclear weapons are the instruments of deterring and preventing a nuclear war. That is how we approach this issue," Russian Foreign Minister Sergey Lavrov said last year.