Since the return of democracy, Argentina has also turned into strong proponent of enhanced regional stability in South America, the country revitalized its relationship with Brazil; and during the 1990s (after signing the Treaty of Peace and Friendship of 1984 between Chile and Argentina) settled lingering border disputes with Chile; discouraged military takeovers in Ecuador and Paraguay; served with the United States, Brazil and Chile as one of the four guarantors of the Ecuador–Peru peace process. Argentina's reputation as a mediator was damaged, however, when President Menem and some members of his cabinet were accused of approving the illegal sale of weapons to Ecuador and to Croatia.