The largest internet portal in Japan, Yahoo! Japan in is set to tie with Google for integrating its search engine technology to the portal. Yahoo! Japan chose Google over Microsoft is surprising because Microsoft under a global partnership is set to offer its search technology to the company.

The alliance between Yahoo and Google will create a dominating portal in Japan and will be a big bow to Microsoft, according to experts. The deal between the two is expected to be announced as soon as Tuesday.

The alliance will almost control whole of the Japanese search market. Yahoo! Japan has a 56 percent share of the search market in the country while Google has a market share of about 31 percent. Microsoft has a share of only three per cent in the country.

Yahoo! Japan has not been affected with an earlier global deal between Microsoft and Yahoo! for search engine market in order to compete with Google. The Yahoo! Japan works independent from the parent company and is not subjected to tie with Microsoft.

In the US, Microsoft’s Bing technology will power the Yahoo search by the end of the year and will also extend to other countries where Yahoo is present.  

Microsoft will most likely try to block the deal between Yahoo! Japan and Google on regulatory grounds. "This agreement is even more anti-competitive than Google's deal with Yahoo in the United States and Canada that the Department of Justice found to be illegal," said Microsoft's general counsel in a statement.

Yahoo! Japan spokesman said that the site has been using Yahoo! Search Technology, since 2004 and it was using Google before that time. The company is expected to announce its quarterly earnings on Tuesday.

Yahoo Japan President Masahiro Inoue indicated that an investigation has revealed the search engine technology from Microsoft is strong in areas such as Japanese language search. Even as being independent, Yahoo Japan has expressed that Yahoo Inc will continue to hold a strategic stake in the company.