Conversation so far:
What did Alberto Fujimori do in his second term as President of Peru?
During his second term, Alberto Fujimori and Ecuadorian President Sixto Durán Ballén signed a peace agreement with Ecuador over a border dispute that had simmered for more than a century
What role did Alberto Fujimori play in the peace agreement with Ecuador over a border dispute that had simmered for more than a century?
The treaty signed by Alberto Fujimori allowed the Peru and Ecuador to obtain international funds for developing the border region.

Question: What border was being disputed?
Self-contained rewrite: What border was being disputed with Ecuador for more than a century?