FRANKFURT (Reuters) - The wealth disparity in the euro zone is increasing, with rising property prices helping Germans get richer while southern European countries lag behind, a study has found.

While the gap between northern countries, such as the Netherlands, and southern states like Portugal has long been a feature of the euro bloc, the study by an arm of German fund manager Flossbach von Storch shows it is getting ever wider.

Taking a basket of items including property, stocks, art and expensive wine, the research concluded that wealth in Germany and Austria jumped more than 7 percent at the end of 2015 compared to a year earlier.

That was roughly twice the growth rate of Italy and Spain, while Greeks saw their wealth drop by more than 4 percent. Property prices, which, for example, jumped by more than 6 percent in Germany, are the biggest driver of wealth.

This difference leads to political tension in the 19-member euro zone, while weak property prices in southern countries hit their banks, which hold homes and commercial property as security for loans.

“Until 2006 when the bubble burst, countries in the south were really taking off. Now they are in a Japan-like situation,” said Thomas Mayer, founder of the research institute that carried out the study.

Japan has long struggled with a largely stagnant economy and ever higher government debt. Some economists fear a similar fate awaits countries in Europe.

“Countries in the north had not had such a strong inflation and came out of it better,” said Mayer.

The European Central Bank has acknowledged this general trend, saying that the gap between weaker and stronger countries in the euro zone was widening rather than narrowing, as originally envisaged when the currency was created.