UK politicians should stop blaming immigration for the country's difficulties, the EU justice commissioner has suggested.
Instead, they should "work on the quality of education and welfare", Viviane Reding said.
In a speech at the University of Cambridge, she renewed her criticism of the "distorted" debate about the UK's future in the European Union.
She claimed it was distracting from vital efforts to boost EU economies.
Prime Minister David Cameron has pledged to negotiate reforms to the UK's relationship with the EU and then deliver an in/out referendum by 2017 if the Conservatives win the 2015 general election.
But Ms Reding said: "The four freedoms enshrined in the EU treaties come as a package.
"You either enjoy all of them - or none. Those who benefit from the free flow of capital, goods and services must also accept that our citizens are free to move in the EU to travel, study and work."
She continued: "Politicians also need to work on the quality of education and welfare, so that people in this country can find employment and enjoy reasonable social standards.
'Inexorably drifting away'
"Simply trying to project all problems on the supposed issue of too many foreigners moving into the country is certainly not the answer.
"It is not EU policies that are causing problems in this area. But somehow this misconception prevails, and there is a sense that all difficulties could be solved if the UK could get out of them, that it needs to free itself of supposedly 'alien', harmful rules and principles that are imposed on it."
Eurosceptic arguments that the UK would be "leaner and meaner" outside the EU ignored that it would face huge problems negotiating favourable deals to access the single market, the commissioner claimed.
The UK appeared to be "gradually, inexorably drifting away" from the EU, she said.
"The debate in this country about the UK's place in the EU is distorted. All that talk about opt-outs, renegotiations and referenda distracts from the real issue.
"Unfortunately, the debate is distracting from the real challenge in the relationship between the UK and the EU. And it is even inflicting wider damage by holding back our Union as a whole.
"We don't need this. What we need are great ideas and solid arguments about how we can strengthen the EU and make it more competitive on the world stage."