President Donald Trump opened up another front in his tussle with allies on his arrival at NATO’s annual summit, targeting Germany over its support for the Nord Stream 2 gas pipeline from Russia.

“It’s very sad when Germany makes a massive oil and gas deal with Russia where we’re supposed to be guarding against Russia and Germany goes out and pays billions and billions of dollars a year to Russia,” Trump said before meeting with NATO Secretary General Jens Stoltenberg on Wednesday morning.

“If you look at it, Germany is a captive of Russia, because they supply --- they got rid of their coal plants, got rid of their nuclear, they’re getting so much of the oil and gas from Russia. I think it’s something NATO has to look at.”

Seen Tweets

German Defense Minister Ursula von der Leyen responded to the Nord Stream criticism in a BBC interview at the NATO summit in Brussels: “We can cope with it. We’ve heard him before and seen the tweets. We have an independent energy supply, we are an independent country, we are just diversifying.”The broadside came at the opening of a two-day summit of North Atlantic Treaty Organization leaders that risks being overshadowed by Trump’s public questioning of the value of the generations-old alliance. The president, who is due to meet with Russian President Vladimir Putin in Finland next week, has linked U.S. spending for Europe’s defense with America’s trade deficit with the world’s largest trading bloc.

Owe Us

“Many countries owe us,” Trump said in Brussels, before attending the summit at NATO headquarters. “The United States is paying far too much and other countries are not paying enough... This has been going on for decades, for decades, it’s disproportionate and not fair to the taxpayers of the United States.”

The combative rhetoric suggests this summit may follow the trajectory of last month’s Group of Seven meeting in Canada. Trump aired his gripes about trade with Canada before traveling to the G-7, and dramatically withdrew his name from the summit’s negotiated communique to protest critical comments by Canadian Prime Minister Justin Trudeau after the meeting. Trudeau and German Chancellor Angela Merkel will both attend the NATO talks.

“NATO is an an alliance of 29 nations and sometimes there are differences and different views and also some disagreements, and the gas pipeline from Russia to Germany is one issue where allies disagree,” said Stoltenberg. “But the strength of NATO is despite these differences we have always been able to unite around our core task, to protect and defend each other, because we understand we are stronger together than apart.”

Still, Poland’s Foreign Minister Jacek Czaputowicz suggested that Trump has a point on the Nord Stream pipelines. “Some countries are too close” to Russia, he said on a panel at a parallel event to NATO, accusing the pipelines which transit gas to western Europe under the Baltic Sea of funding Russia’s military buildup.

Turkey’s Foreign Minister Mevlut Cavusoglu also took a pop at Germany, complaining that Merkel’s government withdrew its patriot missile system from Turkey’s Syrian border. When German Defense Minister Ursula Von der Leyen responded that it was a rotation and Germany stayed 3-4 years, Cavusoglu said: “Italy has been prolonging, like a real ally.”