Transcript for Trump heads to the U.K.

We're gonna start with president from heading to London this morning fresh from that. Contentious. NATO summit in Brussels to president stunned world leaders by open ailing questioning the purpose of NATO. He demanded that America's closest allies dramatically increase defense spending and slammed Germany as being totally controlled by Russia. And this morning he is back on Twitter. And all this just days before his one on one meeting with Vladimir Putin. ABC's Molly hunter is following the developments in the London where this anti front protesters are coming out in force this morning good morning Molly. Chad good morning that thread it's been a wild ride president John continues to insist that NATO allies pay more than are already paying but that's left longtime allies and diplomats just dumbfounded. By the barrage of attacks. And Brussels this morning it's eight to president jumper arriving at NATO headquarters. After a bizarre first day at this summit capped off by this rather bizarre performance Wednesday night. Confusing as the world leaders attempted another family photo. The First Lady right there by her husband's side. President champ greeting France's First Lady and smiling with French president Manuel Mack kral just hours after blasting America's European allies. President chuck accused Germany of being held captive by Russia Germany as far as I'm concerned. The Russian leader trying to make nights we have a very very good relationship with. Chancellor but German Chancellor Angela Merkel just reaffirmed her commitment to the alliance on target for the but he's been typical French president Manuel Matt -- did the same sort of don't go yeah yeah. And British prime minister to reason they did the same later this is. Like to twist day classes have. It has been president Trout flies to London this morning an across the UK antitrust protests are planned London is gearing up for the biggest protest in years. An activist and made this trump BV balloon which will fly over the city tomorrow. That straight line and authorities are planning for huge numbers tomorrow guys but the real highlight might be president chance meeting with the queen at Windsor Castle. Kind of glad we can welcome president chat with them all meat London summer weather when he's they have racing goes gray clouds Molly hunter live in London this morning thank smiling.

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