The frontrunner for the European Union's top job told CNBC that it would not be fair to reassure people that the economic crisis is over.
Jean-Claude Juncker, the former Prime Minister of Luxembourg, is the leader of the European People's Party (EPP) and the favorite to win the position of EU Commission head at the May 22-25 European parliamentary elections.
If successful he will take the helm at a time when many investors have turned more positive on the euro zone's economic prospects. However, Juncker said it was not yet time to call an end to the crisis.
"[With] high unemployment, mainly concerning young people in Europe, you cannot tell people in Europe that the crisis is over. The crisis is over if unemployment comes down," he told CNBC on Wednesday.
Unemployment remains close to record highs across Europe, logging 10.6 percent in February. Over a quarter of Greece and Spain's populations are out of work.
Juncker, who is one of Europe's longest serving politicians, also commented on the rising popularity of anti-European populist parties in Europe, which he acknowledged was a "concern."
"I think that the growing un-acceptance of the E.U., in parts of the European public opinion, is due to the way we are handling the crisis and the way we are dealing with the crisis," he said.
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"[But] the main explanation is that those political forces - mainly those of the extreme right [are] rejecting everything and everyone that is not like them," added Juncker.
In a number of countries across Europe, right wing nationalist parties are gaining an increasing proportion of the electorate's favor, amid growing disillusion with Europe's institutions.
But Juncker said these parties were providing overly simplified answers to very complicated problems.
"You have to make a distinction between those in Europe who are putting wrong or right or unjustified questions to Europe," he said.
"You have to respond to these questions and argue with them because they are not, as a matter of principle, against European integration, but they are of the opinion that part of European policy is not the right one," he added.
On Sunday, Juncker warned Britain's Prime Minister David Cameron against any attempt to limit freedom of movement across the union.
Cameron has clashed with Brussels in the past over tougher rules for migrants claiming benefits in the U.K., but Juncker said he would refuse to renegotiate the core value of freedom of movement across the 28 member states.
Juncker is competing against Socialist candidate Martin Schulz for the role of E.U. Commission head.
This year the seven political groups in the European Parliament have been asked to put forward candidates for the job, marking a break from the previous regime, when the heads of state were responsible for appointing a President of the Commission.