Google has announced concerns over Microsoft's recent bid for Yahoo! and has offered its online rival assistance to ward off the potential takeover.
In a statement yesterday on the company's blog, Google senior vice president, David Drummond, said that "Microsoft's hostile bid for Yahoo! raises troubling questions" for the future of the internet.
"It's about preserving the underlying principles of the internet: openness and innovation," said Mr Drummond.
The comment follows Microsoft's general counsel Brad Smith's announcement yesterday said: "The combination of Microsoft and Yahoo! will create a more competitive marketplace by establishing a compelling number two competitor for internet search and online advertising."
"The alternative scenarios only lead to less competition on the internet," Mr Smith added.
Microsoft's $44.6 billion (£22.4 billion), or $31 (£16) per share, bid for Yahoo! is widely expected to get the go-ahead from regulators.
At the same time, however, it is unlikely that Google will be able to get approval to make a direct counter-offer; its already large market share could provoke competition concerns from anti-trust authorities.
According to the Wall Street Journal, Google chief executive Eric Schmidt called Yahoo! co-founder and chief executive Jerry Yang to offer help in thwarting Microsoft's bid.
Yahoo! reportedly believes that Microsoft's offer undervalues the company, Google's assistance could raise pressure on Microsoft to raise its offer.
Alternative bidders, such as AT&T and News Corp, are not expected to make rival offers for the company.
Yahoo!'s share price leapt almost 50 per cent after Microsoft's announcement last Friday, while Microsoft shares slid 6.6 per cent to close the day at $30.45 (£15.23).