TEHRAN, Iran — Iran said today it plans to build 10 new uranium enrichment sites inside protected mountain strongholds, with construction on the first starting in March, in continuing defiance of international efforts to curb its nuclear development.

Enriching uranium creates fuel for nuclear power plants but can also, if taken to higher levels, produce the material for weapons, and Iran's growing capacity in this process is at the center of its dispute with the international community.

The U.N. Security Council has already passed four sets of sanctions against Iran to try and force it to stop enriching uranium.

Last year, Iran flouted international concerns by claiming it would build 10 new enrichment plants and today's announcement said the locations for the sites have now been determined but gave no details.

"Construction of a new uranium enrichment site will begin by the end of the (Iranian) year (March) or early next year," Salehi said. "The new enrichment facilities will be built inside mountains."

Revelations a year ago of a previously undisclosed enrichment facility in a secret mountain base near the city of Qom, inflamed international suspicions over Iran's enrichment program and helped spur a fourth set of international sanctions in June.

By The Associated Press