* Vale seeking legal review of royalty payments
* Gov't source sees Vale owing up to $2.4 bln
Vale, the world's largest iron ore miner, insisted it had made payments according to the law and said it disagreed with the government over criteria for calculating what it owed.
Analysts say the dispute, which comes as Brazil mulls an increase in mineral royalties that would boost government revenues from the booming mining business, is unlikely to financially harm the company or hinder its operations.
"Vale believes that the values being charged ... are excessive and should be submitted to (review of) judicial experts," the company said in a statement. "Discussions of the correct interpretation of laws are perfectly legitimate."
The firm said the government agency that collects royalties had in some cases considerably lowered requested payments when the company challenged them.
A source at the Mines and Energy Ministry told Reuters on Thursday that the disputed amount could reach 4 billion reais ($2.4 billion). A second source said that figure was the accumulation of a number of royalty disputes dating back years.
The sources said Mines and Energy Minister Edison Lobao had requested a review of pending mining royalty debts and had met with President Dilma Rousseff about the Vale dispute.
Authorities in the northern state of Para had sought to suspend Vale's license to operate the giant Carajas iron mine over the unpaid royalties, though that decision was quickly overturned by the same agency, Vale said.
Operations at Carajas were not affected, according to a company spokeswoman. Analysts for brokerage Ativa said in a research note on Thursday the dispute was unlikely to affect future operations at Carajas or to be resolved quickly.
The royalties in question relate to minerals extracted in Para, where Carajas is located, and in the state of Minas Gerais in the south east.
(Reporting by Leo Goy in Brasilia and Brian Ellsworth in Rio de Janeiro; Editing by Lisa Shumaker)