Search engine Yahoo has announced plans to trial Google AdSense for Search service, which will deliver relevant Google ads alongside Yahoo's search results.

The two-week test will apply only to traffic from Yahoo users in the US and will be limited to no more than three per cent of Yahoo search queries.

Furthermore, it will not include Yahoo's extended network of affiliate or premium publisher partners.

According to Yahoo, the move is part of its exploration of strategic alternatives to maximise stockholder value, including exploration of potential commercial business arrangements.

By collaborating so closely with Google many are seeing this as deliberate slight to Microsoft, which has launched an aggressive take-over bid for Yahoo in an attempt to counter Google's dominance in the search engine market.

Microsoft has expressed concern that any potential deal between Yahoo and Google would give Google a more than 90 per cent share of the search advertising market, thereby raising competition and regulatory issues.

Yahoo has stressed that the trial does not necessarily mean that Yahoo will join the AdSense for Search program or that any further commercial relationship with Google will result.

However, following threats from Microsoft regarding the potential acquisition, many analysts believe Yahoo is searching for as many friends as possible to stave of Redmond's advances.