UPDATE 3-Brazil's Lula to meet with miner Vale CEO

* Lula to meet with Vale CEO as tensions mount

* Brazil considering iron ore export tax

* Measure would hit mining giant Vale (Adds Lula, Vale comments, updates stock price)

By Raymond Colitt

BRASILIA, Oct 16 (Reuters) - Brazilian President Luiz Inacio Lula da Silva said on Friday he will meet the head of mining giant Vale next week amid tensions between the company and the government, which may slap an export tax on iron ore.

Vale (VALE.N)(VALE5.SA) has faced harsh criticism in recent months from government leaders, including Lula, for not investing enough in Brazil, fueling speculation he is seeking to force out the company's chief executive, Roger Agnelli.

Lula said Vale was preparing to announce another set of investments, without offering details, only days after the company unveiled more than $5 billion in new outlays in efforts to stave off the torrent of criticism.

"I'm going to meet with him on Monday in Sao Paulo, where he's going to present Vale projects -- they're important investments, I'll wait for him to announce them," Lula said during a televised address.

A Vale spokesman declined to comment on whether Agnelli would indeed meet with Lula or if the company was going to announce new investments.

Brazil's government is studying creating an export tax on iron ore, a government source said on Friday, possibly making Brazilian ore less competitive in global markets as miners including Vale and Australian giants BHP Billiton (BLT.L) (BHP.AX) and Rio Tinto (RIO.AX)(RIO.L) gear up for benchmark pricing talks.

"There are studies under way but no decision has been taken yet," the source said, adding several ministries would be involved in deciding whether to implement the tax.

The export tax would be preferable to a tentative proposal by government officials to increase mining royalties, the source said, because the latter would affect the steel industry and boost costs throughout the supply chain. The levy would help the government compensate for declining tax revenues.

MARKETS SHRUG

The tax may be up to 5 percent, reported O Globo newspaper. It also suggested the tax was partly aimed at prodding Vale into investing more in value-added products such as steel instead of solely exporting raw materials such as iron ore.

Planning Minister Paulo Bernardo played down the talk of a possible export tax, saying in Sao Paulo that he had only heard the governors of some mining states discuss something similar.

Markets largely shrugged off the news. Vale's stock dipped 0.12 percent to 40.14 reais on the Sao Paulo stock exchange in late afternoon trading compared to a 0.53 percent decline in the benchmark Bovespa index.

A new tax would make it harder for Vale to expand into the growing ore market in China, the world's largest steel producer, said steel and metals analyst Charles Bradford of Bradford Research Inc.

"Brazil's ore has to compete with Australian ore, which is a lot closer to China -- a tax would clearly make Brazilian ore less competitive," said Bradford.

He said the Australians could use this as an excuse to push for higher prices at the upcoming talks, but they could take advantage of the cost increase for Vale to push for greater market share in China by offering better prices.

O Globo this week reported that Lula told top advisors to push for Agnelli's ouster.

Vale, a former state-owned company privatized in the 1990s, is run by a partnership between Brazilian Bank Bradesco (BBD.N)(BBDC4.SA), Japanese trading house Mitsui (8031.T), and a consortium of Brazilian state-controlled pension funds. (Writing by Brian Ellsworth, additional reporting by Denise Luna in Rio de Janeiro and Carmen Munari in Sao Paulo; Editing by David Gregorio)