Google's web mapping service may be blocked in China next year if the search giant refuses to move its mapping server to the Chinese mainland for official licensing.

The State Bureau of Surveying and Mapping has designated March 31 as the deadline for application, and any unlicensed web mapping service providers still in operation on July 1 would be punished, Wu Jiang, the spokesman with the bureau, said Monday.

"There is a possibility that those unlicensed mapping service providers will be closed down or blocked," Wu said.

Online map service providers were required to get licensed with the bureau starting May this year. Non-Chinese web map service providers are required to form a joint venture with a local firm and locate their data server in the Chinese mainland to undergo regular inspections for possible leakage of confidential information.

Google Maps is still in talks with the bureau on the license issue, said the bureau's Wu, who declined to say whether Google had decided to move its server to the mainland. Google closed its China website and transferred its servers to Hong Kong in March this year, after deciding it no longer wanted to censor search results.

The government asks mapping service providers to be staffed with mapping examiners, who would be trained by the bureau to sanitize territorially incorrect or sensitive military information, according to the bureau.

The bureau has so far issued licenses to about 50 web firms. The bureau also awarded itself a license to run Map World, a web-mapping portal launched late November. "Map World could be used to fill the market vacancy if Google Maps is discontinued," said Lai Bin, the editor in chief with Beijing-based IT magazine Net Friends.