San Francisco, New York: Yahoo Inc, which was widely believed to be running out of alternatives to accepting Microsoft Corp's takeover offer, has become a target of two warring camps of technology giants and their media allies, sources said on Wednesday.

News Corp is considering joining Microsoft in a bid for Yahoo which would bring in News Corp's MySpace online social hangout and create a more formid-able rival to internet juggernaut Google Inc, newspaper reports said.

But Yahoo, which announced earlier on Wed-nesday it plans to test Google search ads alongside Yahoo Web search services, is closing in on a deal with Time Warner Inc with its AOL unit, several sources said.

The game of musical chairs among the titans of the internet follows two years of on-again, off-again talks to strike industry-reshaping mergers among different configurations of the same players.

Google, unaccustomed to being backfooted by its rivals, is considered a secondary player unlikely to enter the merger bidding as its growing dominance in web search and search-based advertising could be blocked by competition regulators.

Structure sketchy

Reports were sketchy on exactly how a Microsoft deal with News Corp might be structured, making it difficult for Wall Street analysts to say which combination might prove the superior offer. Several said Yahoo has regained some of the negotiating momentum it appeared to have lost with Microsoft.

But UBS analyst Benjamin Schachter said neither an AOL deal nor a reported plan by Yahoo to buy back a chunk of its shares had enough funding to satisfy shareholders clamouring for a deal worth at least Microsoft's current offer of $31 a share.

"I still think Microsoft holds the cards and the cash," Schachter said.

Yahoo's talks with Time Warner are getting near to a deal that would fold AOL's business, excluding its legacy dial-up internet access operations, into a combined Yahoo company, a person familiar with the talks said. Such a deal would value AOL at $10 billion, the person said.

Yahoo would receive cash from Time Warner in exchange for 20 per cent of a combined Yahoo-AOL, the source said. Other sources confirmed the outlines of the talks but provided no further details.

The Wall Street Journal cited sources saying Yahoo would use the Time Warner cash and other funds to buy back several billion dollars worth of Yahoo stock at a price somewhere in the middle of the range between $30 and $40 a share.

The New York Times reported that Microsoft had begun talks to bring News Corp in on its effort to acquire Yahoo.

Combination

This combination would bring together three of the biggest website publishers on the internet: Yahoo, Microsoft's MSN and News Corp's MySpace, creating a formidable counterweight to Web pacesetter Google, but also drawing antitrust scrutiny.

"The whole situation seems to be very unstable," said Sanford C. Bernstein analyst Jeffrey Lindsay, adding that Microsoft's bid for Yahoo precipitated a cascade of offers.

"There are so many pent-up moves for consolidation but it's hard to say what moves will be successful," Lindsay said.

Yahoo said it was beginning a two-week test on whether it can use Google to sell ads alongside Yahoo web search services. The initial test is small, covering only three per cent of web searches performed on Yahoo, the companies said.

But sources said the tests could lead Yahoo to a broader deal in which it lets Google sell search advertising for it in order for Yahoo to concentrate on online brand ads.

Lindsay has estimated that, by turning over search ad sales to Google, Yahoo could boost its revenue by 10 per cent and free up money to invest in stronger businesses.

Microsoft general counsel Brad Smith said Yahoo and Google would consolidate more than 90 per cent of the search ad market in Google's hands.

Herb Kohl, the Democratic head of the US Senate antitrust subcommittee, chimed in to say he was watching Yahoo's deal closely to ensure it does not harm competition.

Any of the combinations, or another yet to be determined, would fundamentally change the web. Major players have been circling each other as the first decade of growth in the internet market has begun to slow dramatically.