Barack Obama offered solidarity with Greece over its debt and migrant crises on Tuesday during his final trip to Europe as U.S. president before handing over power to Donald Trump.
Obama delighted his Greek hosts by supporting debt relief for the recession-battered country, which has seen its economy shrink by a quarter in just seven years, but riot police had to use teargas to quell anti-U.S. protesters in central Athens.
Greece hopes Obama will be able to persuade its foreign creditors to restructure some of its debt, which stands at nearly 180 percent of national output.
"We cannot simply look to austerity as a strategy," Obama said after talks with Greek Prime Minister Alexis Tsipras.
"Our argument has always been that when the economy contracted this fast, when unemployment is this high, that there also has to be a growth agenda to go with it and it is very difficult to imagine the kind of growth strategy that's needed without some debt relief mechanism," Obama said.
Athens signed up to a third economic bailout package of up to 86 billion euros ($93 billion) in mid-2015 but says it needs a long-term debt restructuring to exit the crisis - a message repeated on Tuesday by Tsipras, a leftist whose popularity is waning.
Obama, who said the United States would stand "shoulder to shoulder" with Greece, a NATO ally, was due to visit Germany on Wednesday, the main champion of economic austerity in Europe.