Chile's CorpBanca SA's (BCA, CORPBANCA.SN) shareholders on Tuesday approved a $600 million capital increase with the proceeds earmarked to finance part of the purchase of Colombia's Helm Bank SA (PFHELMBAN.BO).

CorpBanca, Chile's fifth largest bank in terms of loans, has been aggressively expanding in Colombia, where it purchased the Colombian unit of Spanish bank Banco Santander SA (SAN, SAN.MC) for $1.23 billion earlier this year and will close the acquisition of Helm Bank, valued at $1.28 billion, next year.

The increase will take place between late 2012 and early 2013, the bank said in a statement.

The International Finance Corp., the private-sector financing arm of the World Bank, will subscribe part of the increase by acquiring the stocks the Chilean bank's controllers won't subscribe as part of their pre-emptive rights option.

The IFC will purchase an equity stake in CorpBanca valued at $225 million.

With the acquisition of Helm Bank, CorpBanca plans to increase its loan portfolio in Colombia to $8 billion from $3.63 billion at the end of August and to have a 7% market share, from the current 3%.

CorpBanca shares were recently trading 0.7% lower at 6.30 Chilean pesos (one U.S. cent), while the select IPSA index was 0.06% higher.

In the past 52 weeks, CorpBanca has traded at a high of CLP7.40 and a low of CLP5.50.

Write to Graciela Ibanez at graciela.ibanez@dowjones.com