"It is unacceptable that they have a turnover of several billion euros in France without paying tax," he told Le Point magazine, adding that the French government should consider taxing online advertising revenues.

French lawmakers last year rejected plans for a proposed tax on online advertising revenues, fearing the project would hurt small local companies more than global Internet giants like Google, Facebook or Twitter.

A spokesman for Google hit back, arguing that "the Internet offers a wonderful opportunity to generate growth and jobs in France".

Google cited a report from management consultant McKinsey that said Internet companies contributed 60 billion euros ($78 billion) to the French economy in 2009, or 3.2 percent of output, and could create 450,000 jobs by 2015.

"This positive contribution would have a better chance of coming about in an environment that is supportive of the web in France and of investment in the sector. Public policy should support this," the spokesman argued.

The president's comment came as Twitter co-founder Jack Dorsey was in Paris to meet with French presidential candidates, including Sarkozy.

Sarkozy urged Twitter to follow other Internet companies and base their European operations in France, the president's office said.

"Jack Dorsey responded positively to this invitation," it added.

Sarkozy argued that France should not "only be a consumer of digital products, but a creator of digital technology and innovative methods" and pointed out that both Google and Microsoft had recently opened offices in France.

Earlier Dorsey had met the front-running Socialist candidate Francois Hollande and with centrist Francois Bayrou, and he met Sarkozy later in the day.

Hollande's campaign team said the candidate and Dorsey discussed the development of innovative companies in France and the Internet sector.

James Whittaker left Microsoft in 2009 for a high-level software engineering job at Google only to recently jump back to the California-based firm's rival.

In a personal blog post he explained why he left what is considered one of the world's most desirable workplaces.

"The Google I was passionate about was a technology company that empowered its employees to innovate," Whittaker said.

"The Google I left was an advertising company with a single corporate-mandated focus."

That focus was to conquer the online social networking realm where Facebook rules and Google stumbled with offerings such as Buzz and Wave, according to Whittaker.

"Larry Page himself assumed command to right this wrong," he said, referring to the Google co-founder who took over as chief executive last year.

"Social became state-owned, a corporate mandate called Google+," he continued.

Emphasis was put on synching Google+ social network with the company's popular services such as search and online video venue YouTube.

"Like the proverbial hare confident enough in its lead to risk a brief nap, Google awoke from its social dreaming to find its front runner status in ads threatened," Whittaker said.

Google shut down its Labs initiative to support experimental projects and soured on a policy that lets employees spend 20 percent of their time on ideas unrelated to their usual jobs, according to the former 'Googler.'

"As the trappings of entrepreneurship were dismantled, derisive talk of the 'old Google' and its feeble attempts at competing with Facebook surfaced to justify a 'new Google' that promised 'more wood behind fewer arrows'."

Whittaker told of working on Google+ but seeing the social network make little headway against Facebook.

"As it turned out, sharing was not broken," he said. "Sharing was working fine and dandy, Google just wasn't a part of it."

"Google was the rich kid who, after having discovered he wasn't invited to the party, built his own party in retaliation," Whittaker continued. "The fact that no one came to Google's party became the elephant in the room."

Google decline to comment for this story.