After more than a year of negotiations, Argentina's Techint group has emerged as the victor in the chase to buy out shares in Brazilian flat steelmaker Usinas Siderurgicas de Minas Gerais S.A. (USIM4.BR), or Usiminas, which were put up for sale by Brazilian industrial groups Votorantim and Camargo Correa.

The Techint group has offered 36 Brazilian reais ($19) per voting share, which the group said was a premium of 41% over the average trading of the last six months, based in U.S. dollars. The companies said the total cost for the 27.7% of Usiminas's voting shares would be about $2.7 billion.

Ternium had confirmed that it was in talks to buy the stakes on Nov. 17. On that day, it's shares plunged 9%, to $22.99; the shares have since sunk below $19, although they recovered slightly on Friday, ending nearly 4% higher at $19.32.

A number of possible bidders have been rumored to been interested at different points of the process, including Brazilian steelmakers Gerdau SA (GGB, GGBR4.BR) and Companhia Siderurgica Nacional SA (SID, CSNA3.BR), according to the web site of the O Estado de Sao Paulo newspaper.

CSN has over the last year bought up Usiminas shares on the open market, and owns 20% of Usiminas's preferred stock and nearly 12% of voting stock. That had prompted speculation that CSN might be preparing a hostile bid for Usiminas.

The Usiminas shares will be bought by three Techint companies: Ternium SA (TX) and its Argentine subsidiary Siderar SA (ERAR.BA, SDDFF), and Confab Industrial SA, a subsidiary of another Techint company, Tenaris S.A. (TS, TEN.MI).

Ternium and Siderar will finance their BRL4.1 billion share, equivalent to about $2.2 billion, with cash on hand and debt, Ternium said in a statement. Confab has agreed to buy 5% of voting shares at a total cost of around $500 million, Tenaris said in a statement.

The three buyers will join the group of controlling shareholders, which also includes Nippon Steel Co. (5401.TO, NISTY) and the Usiminas' employees union, Caixa dos Empregados Usiminas, or CEU. As part of the transaction, Nippon Steel plans to increase its stake in Usiminas, buying a further 8.5 million ordinary shares from CEU.

The transaction is expected to close in January 2012, Tenaris said.

Camargo Correa and Votorantim have reportedly been looking to sell their Usiminas stakes for some time. Votorantim on Sunday said that it wants to concentrate on their core businesses, including cement, cellulose, orange juice and long steel.

Meanwhile, there's been speculation that Ternium may now pull out of its plans to build a steel mill in the Acu port of LLX (LLXL3.BR), owned by Brazilian billionaire Eike Batista. The UBS investment bank recently said that fast-growing oil industry business could "more than offset" the potential withdrawal of Ternium.

-By Matthew Cowley, Dow Jones Newswires; +55 11 3544 7082; matthew.cowley@dowjones.com