By Eugene Scott

CNN

(CNN) -- Tension between Germany and the United States intensified Tuesday with President Donald Trump accusing the longtime US ally of hurting the US financially.

"We have a MASSIVE trade deficit with Germany, plus they pay FAR LESS than they should on NATO & military. Very bad for U.S. This will change," he tweeted.

Trump's recent run of criticism aimed at Germany began last week at a G7 meeting, in which the President blasted traditional US allies over NATO obligations and made clear that he was more than willing to go it alone on climate change and trade.

In turn, German Chancellor Angela Merkel suggested over the weekend that her country's relationship with the US had shifted.

"The times when we could completely rely on others are, to an extent, over," Merkel said at a beer hall rally to support her campaign.

Merkel did not mention Trump specifically, but she made it clear that her realization had come "in the last few days."

Questioned about her comments Tuesday, Merkel reiterated her stance: "the discussions with the USA are just as important as with other partners -- the transatlantic relations is of incredible importance, but what I said at this current point in time is that there are more reasons than there even were before to take our fate into our hands in Europe."

German Foreign Minister Sigmar Gabriel also criticized Trump's policies toward refugees and immigration, saying they put Europe's peace at risk.

"Anyone who accelerates climate by weakening environmental protection, who sells more weapons in conflict zones and who does not want to politically resolve religious conflicts is putting peace in Europe at risk," he said on the sidelines of the third Berlin roundtable discussion on refugees and migration Monday. "The short-sighted policy of the American government is against the interests of the European Union."

CNN's Sarah Chiplin contributed to this report.