Google Inc., fighting to consolidate its trademark globally, faces an obstacle in the world’s second largest Web market — China’s www.Gmail.cn, which is refusing to sell its Internet address to the U.S. giant.

A legal source told Reuters on Monday that Google was trying to buy the Internet domain name www.gmail.cn, which is run by Beijing-based ISM Technologies.

The name closely resembles Google’s internationally known email service, www.gmail.com, and the colors in which the two logos are written are similar. The “.cn” suffix is commonly used for Chinese domain names.

Google recently began offering free Gmail accounts in China to promote its brand among local users.

“Google has contacted Gmail.cn about the Web address and logo issue, but there is no progress so far,” said a legal source in Shanghai familiar with the situation.