MOUNTAIN VIEW,  USA: Google Inc co-founder Sergey Brin said on Tuesday it has become "very hard to operate" in China, but he is optimistic that the Internet company can continue to "open up information for everyone everywhere, free of political censorship."

"In the past couple of years, especially since the Olympics, the situation has gotten considerably worse on a variety of fronts," Brin told Reuters.

Google sent shockwaves across business and political circles when it declared on Jan. 12 it would stop censoring Chinese search results, and said it was considering pulling out of the country.

Brin's comments are among the first by senior Google management on the issue since the announcement.

He said that not only has information been omitted from the company's core search service in China, but also other Google products as well.

"Other sites of ours, such as YouTube and Google Docs ... are blocked," Brin noted.

Asked whether Google was in direct communication with the Obama administration regarding these issues, Brin would only say "there have been a lot of parties that have responded to our blogpost and offered interest."

Brin, who grew up in the former Soviet Union and controls the majority of Google's voting shares with co-founder Larry Page, said Google has had an important impact on China since it entered the market in 2006.

"The initial momentum that we saw hasn't really continued, and it's made it very hard to operate under these kinds of circumstances," Brin said, adding he had no new information to share about discussions between China and the Internet search leader.