(Bloomberg) -- In an unexpected twist, NATO leaders are holding an unplanned emergency session on the last day of their two-day summit, which has been upended by U.S. President Donald Trump’s attacks on allies over defense spending.

We are following developments here in real time. Time stamps are for Brussels.

Some context (11:40 a.m.)

Trump used the session with Ukraine and Georgia to return to the question of NATO members’ defense spending and used a “harsher” tone than yesterday, according to a European official with knowledge of the discussion. He targeted Germany in particular and referred to “Angela” more than once, saying something to the effect that she can do more. He also apparently referred to the cost of the new NATO headquarters. As a result of this twist, Secretary General Jens Stoltenberg called a session of the NATO leaders.

Trump set the tone last night with a tweet: “What good is NATO if Germany is paying Russia billions of dollars for gas and energy? Why are there only 5 out of 29 countries that have met their commitment? The U.S. is paying for Europe’s protection, then loses billions on Trade. Must pay 2% of GDP IMMEDIATELY, not by 2025.”

Trump has quipped about the U.S. going it alone before, only to have the administration walk back his comments.

Unscheduled emergency meeting (11:26 a.m.)

NATO leaders hold an unscheduled meeting to discuss the alliance budget this morning, officials familiar with the matter said. One of the officials said the meeting takes place against the backdrop of Trump threatening allies to “go it alone” unless if they agree to increase their defense budget immediately. A White House spokeswoman wasn’t immediately available to comment.

Earlier:Trump Sowing Divisions at NATO Seen as Helping Only Russia

--With assistance from Nikos Chrysoloras.

To contact the reporters on this story: Viktoria Dendrinou in Brussels at vdendrinou@bloomberg.net;Jessica Shankleman in London at jshankleman@bloomberg.net

To contact the editors responsible for this story: Flavia Krause-Jackson at fjackson@bloomberg.net;Alan Crawford at acrawford6@bloomberg.net

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