Sharp divisions over who should pay for Europe's defense have overshadowed the opening of the NATO summit in Brussels, after U.S. President Donald Trump accused European allies of taking advantage of American taxpayers.
The U.S. spends about 3.5 percent of GDP on defense, far higher than other member states. It is predicted that eight of the 29 members, including the United States, will meet the NATO target of two percent of GDP this year. The U.S. provides 70 percent of NATO's budget.
But Trump suggested Wednesday that NATO allies commit to spending 4 percent of their GDP on defense by 2024. White House Press Secretary Sarah Huckabee Sanders confirmed that Trump raised the idea at a closed-door meeting with fellow NATO leaders.
"President Trump wants to see our allies share more of the burden and at a very minimum meet their already stated obligations,"said Sanders.
NATO Secretary-General Jens Stoltenberg opened proceedings in Brussels with a clear message: This year's summit would focus on who's paying the bill, or in NATO terms, burden-sharing.
"Fair burden-sharing underpins everything that we do. Just a few years ago we were cutting our defense budgets. Now we are adding billions," Stoltenberg said.
Credit for those added billions is being claimed fully by the U.S. president.
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"Because of me they've raised about $40 billion over the last year. So I think the secretary-general likes Trump. He may be the only one, but that's okay with me," he told reporters as the summit began.
Alliances and friendships are being sorely tested at the meeting of world leaders. Trump accused Berlin of being under the control of Moscow, citing a new pipeline project that will supply Russian gas directly to Germany.
After a seemingly tense bilateral meeting with her U.S. counterpart, German Chancellor Angela Merkel underlined her country's commitment to NATO.
"It's very important that we have these exchanges together because we are partners, we are good partners and we wish to continue to cooperate in the future," she told reporters.
Singling out Germany isn't necessarily fair, said defense analyst Sophia Besch of the Center for European Reform.
"Germany's contributions to NATO go well beyond what it spends on its own defense. Germany is contributing troops as a lead nation in Lithuania and NATO's forward presence to the east," she said.
The feud over defense spending looks set to overshadow other business at the two-day summit. Britain announced it would double its number of troops in Afghanistan, while Canada offered to lead a NATO training mission in Iraq.
"Now we have to rebuild that democracy and strengthen it. NATO is going to take a significant role in that, and Canada is going to commit 250 troops, a number of helicopters, and we are actually offering to command that mission for the first year," Canadian Prime Minister Justin Trudeau announced at the summit.
A joint summit declaration issued Wednesday underlined NATO's support for Ukraine and its aspirations for membership of the alliance, pending domestic reforms. Ukraine is attending the Brussels summit and further discussions are due to take place Thursday.
The declaration also formally extended an invitation to the former Yugoslav Republic of Macedonia to join, as soon as it reaches an acceptable solution to its naming dispute with Greece.
Georgia's future membership also will be discussed Thursday as the summit continues.