In an interview for CNN, Polish Finance Minister Jacek Rostowski said that Poland wants to become a member of the euro zone but will wait until "it is safe to do so."

The minister said the euro zone must be "repaired" and there is a lot to be done.

"We are very concerned, we think half the job has been done, but we are still not entirely out of the woods. We feel that the so-called firewall is inadequately large and we feel that the freedom of action that the ECB thinks it has is inadequate," said Mr Rostowski, pointing out that there needs to be fewer restrictions on the European Central Bank, for example when it comes to buying government bonds.

These comments came after data showed on Wednesday that unemployment in the euro zone for March, at 10.9 percent, grew for the 11th consecutive month in a row.

Over 17 million people in the common currency area were unemployed in March, with wide gaps between northern and southern countries. According to Eurostat figures, unemployment in Germany stood at 5.6 percent, and over 24 percent in Spain.

Poland A.M.