Microsoft is to take over ciao.com in order to try and boost its struggling European market share in online search.

The software giant has agreed to buy Greenfield Online, parent company of the European price comparison website, for around the $486 million mark.

Microsoft told Reuters the purchase would help it build a "more consumer-friendly, results-oriented search engine" aimed particularly at shoppers.

Caio.com is available in seven countries and claims nearly 20 million unique visitors per month.

The deal is expected to close during the fourth quarter of 2008.