"The currency changeover runs more smoothly than we expected," said Eugenio Domingo Solans of the Board of Governors of the European Central Bank (ECB) on Wednesday.

In Germany, savings banks have handed over some 4 billion euro to customers exchanging German marks, said bank unions.

Over 80 percent of the automated teller machines (ATMs) in the whole euro zone have been ready for customers to withdraw euro notes. In some countries including Austria, Germany, Luxembourg and the Netherlands, all ATMs have been converted to disperse euro instead of old currencies, said ECB officials.

The demand on ATMs was tremendous with four times more customers than usual having withdrawn money over the last two days, they said.

President of German Federal Bank Ernst Welteke expressed his satisfaction with the euro's first two days, saying: "If we now recall what we had forecast about the euro cash's start, we see that the whole process was very smooth."

No big problems occurred since the euro circulation on January 1 although there were some very small ones such as ATMs that swallowed EC-card suddenly, Karin Kuchelmeister of the Federal Association of Consumer Center.

"Surprisingly there were no significant problems with the euro start," reported the German Association of Trade representing medium-sized and big trade companies. It said that there were neither long lines nor problems with change in the busy business day Wednesday.

Half of the customers began to pay with euro on Wednesday afternoon, said spokesman of the retail branch Hubertus Pellengahr.

"The customers like to go shopping with euro," he said.

Euro and German mark can be used together in Germany until February 28 and then euro will be the sole currency.