China has banned foreign tourists from Tibet and other western regions of the country, the official Xinhua News Agency reported Friday amid mounting travel restrictions meant to stop the spread of SARS.

Travel agencies have been told to delay all tourism to the region until the end of May, and tour groups already in China were told to halt any plans to go there, Xinhua said.

The report did not mention severe acute respiratory syndrome, but it came amid sweeping restrictions on travel and other activities in an attempt to stop the spread of the virus.

China has cut short the May Day holiday that began Thursday and banned travel agencies from taking Chinese outside their home provinces. The Xinhua report was the first government announcement to specifically cite travel by foreigners.

The State Tourism Administration stopped approving new applications to travel to Tibet on April 25, Xinhua said. It didn't say why the order was not publicized until now or when it had been delivered to tour agents. The report didn't say when travel to other parts of China's west was banned.

The report also did not specify whether foreign tour groups that were already in Tibet would have to leave immediately.

SARS has killed at least 181 people throughout China.

No cases have been reported in Tibet, but Chinese officials have warned of a potential disaster if the disease spreads into poor regions that lack adequate sanitation and health care systems.