Demand for 3G (third-generation) mobile phones designed for high-speed mobile data service is picking up as phone sizes come down and battery life goes up, according to German market research group GfK AG.

In March, about 225,000 3G phones were sold in Europe, a GfK spokesman announced today. Although that number represents only around two percent of the entire European mobile phone market, it is double the figure in February.

GfK attributes the jump in demand to the introduction of new lighter weight handsets with improved batteries, according to the spokesman.

Europe's first 3G operator, Hutchison 3G (H3G) has struggled to sell early 3G phone models.

At a conference last year, Peter Erskine, chief executive officer of UK mobile phone group mmO2, referred to the initial phones of rival H3G UK as "bricks."

Several new 3G phones are now spurring consumer demand, including the Z105 model from Samsung, the Z1010 from Sony Ericsson and the 7600 from Nokia.

The growing interest among both consumers and business users in 3G should come as a relief to European mobile companies, which spent around €100 billion acquiring pricey licenses.