BOGOTA (Reuters) - The Colombian government sold its 57.6 percent controlling stake in power generator Isagen (>> Isagen S.A. ESP) to Canada's Brookfield Asset Management (>> Brookfield Asset Management Inc) for $1.99 billion, Finance Minister Mauricio Cardenas said on Wednesday.

The stake, sold at the minimum price of 6.49 trillion Colombian pesos, is the largest privatization in the country in nearly a decade.

Isagen shares were up nearly 16 percent, trading at 3,780 pesos per share. Brookfield shares were up 1.23 percent, to$41.88 Canadian dollars.

"The buyer is Brookfield Colombia Investment, part of Canadian investment fund Brookfield Asset Management," Cardenas said. "The price of the sale was 4,130 pesos per share, with which the nation will receive 6.49 trillion pesos."

The government plans to use proceeds to fund highways, bridges and tunnels across the country, its so-called 4G infrastructure projects.

"We are extremely pleased to grow our business in Colombia, an attractive market with strong long-term growth fundamentals, a highly skilled labor force and continued need for new investment," Sachin Shah, president of Brookfield Renewable Energy Partners, said in a statement. Brookfield valued the sale at approximately $2.2 billion.

Brookfield has until Jan. 27 to pay for the company and take possession of the shares, a finance ministry official said. The government was advised on the sale by Credit Suisse.

The sale price was 11.1 times EBITDA and 24.2 times earnings, according to Jaime Pedroza of Credicorp Capital Research.

"Both metrics are above the average of other companies in the current market, which makes the sale price highly attractive relative to other recent sales in the region," he said.

Chile's Colbun (>> Colbun S.A.) withdrew from the auction on Monday, in part because of a 21.5 percent increase in the minimum price, leaving Brookfield as the sole bidder.

The auction has been suspended at least twice because of legal challenges. A last-minute appeal by a left-wing senator was rejected by legal authorities late on Tuesday.

Union members gathered outside the headquarters of the Bogota stock exchange, where the results were announced, to protest the sale.

Brookfield, which has around $225 billion of assets under management, set up a $400 million fund to invest in Colombian infrastructure assets in 2009.

It acquired Transelec, the largest electricity transmission system in Chile in 2006. In 2011, it purchased an electrical distribution business in Colombia and, in 2012 and 2013, it bought toll road networks in Brazil and Chile.

(Reporting by Julia Symmes Cobb and Luis Jaime Acosta, additional reporting by Carlos Vargas in Bogota and Matt Scuffham in Toronto; Editing by Andrea Ricci and Alan Crosby)

By Julia Symmes Cobb