In an exclusive interview with EurActiv, Hammarberg said that Tunisa had been "a model for all refugee policies for the whole world," depsite enormous migratory pressures at its border.
Tunisia has been facing a difficult situation since January's 'jasmine revolution' but has still welcomed more than a quarter of a million refugees from Libya with "open arms," Hammarberg pointed out.
"In contrast, the 500 million Europeans are closing their doors, sending back boats and people coming there, treating those coming into Europe as if they were totally unwanted. I think this is very sad. It is proof that Europe is not living up to its own declarations about human rights," he said.
Hammarberg was presenting his new book, entitled 'Human rights in Europe: no grounds for complacency', at the Centre for European Policy Studies (CEPS) yesterday (4 May).
The human rights commissioner criticised recent moves to re-introduce internal border checks in the EU's Schengen zone for sending negative signals to the rest of the world.
"I do believe that we are facing a very unfortunate situation now when Europe is closing up even more and beginning to resurrect borders inside Europe in order to send negative signals about welcoming refugees and migrants from other parts of the world," he said.
Without naming France or Italy, he criticised the actions of some governments, saying they contravened human rights standards that had already been agreed.
Asked about French President Nicolas Sarkozy, whose actions appear largely to have been motivated by the 2012 presidential election, Hammarberg warned against internal politicking fuelling xenophobia.
"My suggestion is instead of giving in to these kinds of xenophobic tendencies, the leading politicians should stand up and explain why we need to care of people in desperate need in other parts of the world and see this as a task of humanitarian value. But they don't. They back down and they betray the basic humanitarian principles which I thought Europe would honour," he said.
Hammarberg also warned that the problem, which first reared its head last July in France with the mass expulsions of Roma, was far from over.
"It was no solution to arrest them and send them back and treat them badly," he said.
On a separate topic, Hammarberg described as "unfortunate" a decision by the European Commission to give the green light to amendments of a controversial Hungarian media law, despite the Council of Europe taking a more critical view.