The executive chairman of Google has rejected accusations that the internet search company fixed its search results to favour its own products and services.

Eric Schmidt was responding to claims on Wednesday by some members of the US Senate Judiciary Subcommittee's anti-trust panel that Google had grown into a dominant and potentially anti-competitive force on the internet.

"May I simply say that I can assure you we're not cooking anything," he said.

The subcommittee is looking at whether Google abuses its market position while the US Federal Trade Commission is also investigating the same issue.

Google faces a further continuing investigation by the European Commission.

Al Jazeera's Kimberly Halkett, reporting from Washington, said: "Senators accused Google for manipulating search tools, so Google products always end up higher up the search results."

Mike Lee, a Republican member of the senate panel, said during the hearing: "Google is in a position to determine who will succeed and who will fail on the internet.

"In the words of the head of the Google's search-ranking team, Google is the biggest kingmaker on Earth."

Google has been broadly accused of using its clout in the search market to stop rivals as it moves into related businesses, like travel search.

Google is trying to convince regulators and US legislators that it does not need restrictions placed on its growing portfolio, and that its business practices are legal and good for consumers.

Google controls more than two-thirds of the global search market. But Schmidt argued that specialty web sites, like those with restaurant reviews and travel search, give Google stiff competition.

In a reference to Microsoft, which faced nearly two decades of legal scrutiny for anti-trust violations and various fines, Schmidt said: "We get it. By that I mean, we get the lessons of our corporate predecessors."

Schmidt was Google's chief executive officer for 10 years until April this year, when he vacated the post for Larry Page, the company's co-founder, in April.

Schmidt now serves as executive chairman and oversees government affairs.