BEIJING -- Price rises of rare earths are not a result of manipulation by the Chinese government, a senior official said Thursday.

"It's a misunderstanding to think that government manipulation has caused a resurgence in prices," Zhu Hongren, chief engineer and spokesman for the Ministry of Industry and Information Technology (MIIT), said during a press conference.

Considering the huge resource consumption and environment pollution caused by rare earths mining, prices were unreasonably low previously and the recent rises are rational, he said.

Besides, the development of new material industries have increased demand, but the price rises were smaller than those of other commodities such as oil, he added.

Oil prices have ballooned more than five-fold since 1988 while rare earths prices have only tripled, according the spokesman.

Rare earths, a group of 17 metals, are among the most sought-after resources in modern manufacturing. They are vital materials to make an array of sophisticated products ranging from electric car batteries, wind turbines to aerospace alloys.

China suffers serious environmental pollution from mining the metals. More than 90 percent of rare earths on the international market come from China.