In a rancorous speech the EU Commission chief accused the eurosceptic President of giving him the “cold shoulder” and ignoring the role of eurocrats in running European trade negotiations.
Mr Trump has openly stated previously that he prefers dealing bilaterally with countries on a one to one basis and is not a fan of overbearing supranational structures like the EU.
He reportedly pressed Angela Merkel for a swift trade deal during her trip to the White House earlier this year, prompting a bemused response from the German chancellor who replied that all agreements had to go through Brussels.
The billionaire tycoon has also been publicly keen on striking an economic pact with Britain, which will be able to forge its own trade policy for the first time in 45 years once it has left the EU.
Talking about Mr Trump’s attitude towards Europe, the EU chief said: “They say: ‘We do not want to negotiate with you as a European Union but with each member state separately’.
“We cannot allow individual [trade] agreements between the Americans and individual European countries to take place.”
Mr Juncker made his remarks about the US administration just hours after it emerged that it is likely to pull America out of the international Paris Agreement on climate change.