The International Finance Corp (IFC), the World Bank’s private investment arm, is seeking an independent analysis of Brazilian bank Itaú Unibanco Holding SA’s planned takeover of Chile’s CorpBanca, in which the IFC holds a 5% stake.

The IFC needs to give its consent for the deal to materialize, CorpBanca said in a filing with Chile’s SVS securities regulator on Monday night.

The IFC said in an e-mailed comment to Reuters that it “continues to analyze the proposed merger and has not yet determined its position.”

CorpBanca said in a statement that the IFC “has requested an investment bank to evaluate the terms and conditions of the deal.” This is part of the IFC’s analysis of “whether to give (the deal) its consent, a prerequisite for the realization of the transaction,” the Chilean bank added.

The tie-up between regional peers Itaú (ITUB4.SA) and CorpBanca COB.SN, which would be Latin America’s largest banking combination since 2008, has already faced stiff resistance from minority shareholder U.S. investment firm Cartica Management LLC.

Cartica, which oversees about $2 billion in assets and owns about 3.2 percent of CorpBanca’s common shares, has argued that Itaú and CorpBanca’s controlling shareholder, billionaire Alvaro Saieh, violated U.S. anti-fraud and disclosure rules.