Europe must cooperate more closely if it wants the euro to succeed as its shared currency, according to German Chancellor Angela Merkel in her New Year's Eve address.

She said Europe still has a long way to go to overcome its sovereign debt crisis.

The German Chancellor said that she would do everything in her power to strengthen the euro, but that this would only work if Europe learned from its mistakes.

"A common currency can only really be successful if we in Europe cooperate more than we have done," Ms Merkel said in a pre-recorded televised address broadcast this evening.

"Europe is growing together in the crisis," she said, according to an official copy of her speech.

"The path to overcoming this remains long and won't be free from setbacks, but at the end of it, Europe will emerge stronger from the crisis than it went into it."

Ms Merkel also said that while the German economy was doing well, next year would "without a doubt be more difficult than this one".

"In Germany, we have good reasons to be confident," she added, arguing that the country's economic competitiveness had suffered less than its European partners, with the jobless rate in particular at its lowest in 20 years.

The German economy in 2012 is forecast to grow between 0.5% and 1%, much lower than the 3% expected in 2011. It could avoid negative growth and recession predicted earlier by economists for this winter.

One study, by the Allensbach institute published on Thursday showed that 49% of Germans were optimistic for 2012, against 17% who declared themselves pessimistic and 26% sceptical.

The results attracted attention because over the past 12 years of the poll, the optimists have outnumbered the pessimists and sceptics on only four occasions.