This year Barrick experienced a further, unexpected administrative challenge that will be difficult to resolve. After seventeen years in effect, Argentina chose not to renew a bi-national taxation treaty with Chile. The treaty provided the legal framework under which a special tax agreement concerning Pascua Lama was hastily negotiated, after more than three years of conversations between officials and experts from Chile and Argentina. The negotiation took place in 2009, following visits by Aaron Regent to Michelle Bachelet, then President of Chile, and Peter Munk to Cristina Fernandez, President of Argentina. Several Argentine officials, who viewed the agreement as prejudicial to national interests, resigned in protest. Because the tax agreement for Pascua Lama refers to the international treaty, the applicability of the former is thrown into question with the expiry of the latter.