Washington (CNN) Tensions between the Trump administration and Europe are reaching a fever pitch ahead of next month's NATO summit, on the heels of President Donald Trump's announcement of tariffs against European allies and his comments denouncing the transatlantic alliance.

"There is a Trump's hell where NATO is as bad as NAFTA and EU worse than China," a senior European official said. "The transatlantic relationship, which all around the table we consider a given, is not a given."

The official added, "We now have a major crisis."

The official's comments came after the G7 meeting in Canada earlier this month, when Trump told the G7 leaders that "NATO is as bad as NAFTA," according to a diplomat from a G7 country. Axios was first to report the Trump remark, which stands in stark contrast to the sunny image US officials try to convey as they insist that relations with Europe are just fine.

But Trump's announcement that he would slap steel and aluminum tariffs on the EU, Canada and Mexico, and his harsh criticism of those countries, now has many of America's closest allies openly questioning the reliability of the United States. European officials are promising retaliation and are concerned about a trade war.

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