By Michael Bristow
BBC News, Lhasa
Chinese officials have said they will not approve mining operations in Tibet that could damage the environment.
Tibet's natural reserves need to be safeguarded from pollution
They also said mining firms established in the region would have to pay for the environmental damage they cause.
"When there is a conflict between protecting the environment and economic development, protection will come first," said official Zhang Tianhua.
But with mining already described as a "pillar industry", it is unclear how a protection policy would work.
Tibet has abundant mineral deposits, including copper, iron, lead and zinc.
Earlier this year, Chinese geologists announced that they had discovered 16 major mineral deposits along the railway line that connects Lhasa, the region's capital, with the rest of China.
Parts of northern Tibet, again near the railway line, could also contain vast oil and gas reserves, the geologists added in a report carried by state-run Xinhua News Agency.
The discovery of these minerals, coupled with the opening of the railway line last year, has given a boost to the mining industry in Tibet.
Local investment officials recently described mining as a "pillar industry".
And with China needing increasing amounts of raw materials to feed its economy, mining in Tibet looks set to expand.
But Mr Zhang, deputy director of the local environmental protection bureau, insisted that mining companies would not be allowed to pollute the area.
Speaking at the Lhalu wetland reserve on the outskirts of Lhasa, he said the government also planned to ban mining outright for certain metals and minerals. These include gold and mercury.
Local government officials also announced recently that companies wanting to exploit Tibet's mineral resources would first have to pay a deposit.
Although they did not say how much this would be, the money will be used to clean up any pollution caused by the firms' mining operations.
Pollution, however, is not the only concern. Critics also say Tibetans benefit least from mining in the region.
"Under Chinese rule, Tibetans have no voice to determine the use of their own natural resources," according to a statement from rights group Students for a Free Tibet.
Ethnic Tibetans recently staged protests in Sichuan Province because of mining operations at a mountain they consider sacred.