Venezuelan President Hugo Chavez said he’s preparing a decree to give the government exclusive control over gold mining in the country to pare illegal operations and boost international reserves.

Chavez, speaking today on state television, said Venezuela can’t allow illegal miners to continue exploiting deposits rich in gold and coltan, an ore containing tantalum, which is used in mobile phones and video-game consoles.

“The area is run by the mafia,” said Chavez. “We’re going to nationalize gold. We can’t keep allowing them to take it away.”

Venezuela is facing international arbitration over nationalized gold assets from three companies including Crystallex International Corp. (KRY), a Canadian gold producer. Venezuela last year relaxed restrictions on gold exports to allow some private companies and joint ventures with the government to send as much as 50 percent of output abroad.