Transcript for NATO summit set to kick off amid tensions over Trump's comments

However when you're watching ABC news live I'm Terry Moran here in Brussels at the NATO summit NATO has been around almost seventy years but there's never been a summit. Like this when it's quickly turned into a showdown between president trump. And some of the countries which have long been considered America's closest allies Germany in particular. There were all smiles the leaders as they gathered for their family photo looked up. At the helicopter fly by but this morning began on a rocky start president trump with a breakfast tirade directed. Germany in particular. And oddly. A twelve billion dollar pipeline deal with Germany recently struck with Russia president saying that Germany is now out of the total control of Russia his real beef. It's one that other presidents have had. And that is. The argument goes Europeans are freeloading on the American taxpayer not paying their fair share. The massive cost. That NATO incurs. But Europeans worry that goes beyond that president trump called this alliance which has been a cornerstone not just of trans Atlantic security. The trans Atlantic identity for all these decades present trump called it obsolete when he was running for president. And people look at his warm wards and close relations with Russian president Vladimir Putin and they wonder. Is present drop out to reform NATO. Or to end it. It's a big question as they say this summit off to a rocky start it's gonna go for two days and probably feel for some of those leaders like a lot longer. I'm Terry Moran here in Brussels you're watching ABC news line.

This transcript has been automatically generated and may not be 100% accurate.