CARLOS Salinas de Gortari said it was of his own volition that he appeared in Dublin last Monday before Mexican officials investigating a murder of which this brother is accused.
Countering reports that his appearance was in response to a summons, the former Mexican president told The Irish Times that his appearance had been "voluntary".
He had waived his right under Mexican law as a relative of the accused to excuse himself from being questioned in a foreign country "in order to give them the information they want".
The once hugely popular president, now in deep political disgrace, has been living in Ireland for almost 11 months. This week he was accused in Mexico of orchestrating a campaign from Dublin, using the media, to smear prosecutors and weaken the case against his younger brother, Raul.
Analysts have also said that he is planning a political comeback from Dublin.
A source close to the former president, who has been pilloried since a currency crisis threatened economic ruin shortly after he stepped down in late 1994, said Mr Salinas offered to give his evidence in Mexico. But the authorities there preferred the more neutral setting of Dublin.
In an interview with a Mexican newspaper, Reforma, this week he blamed the crisis on a huge power struggle within the ruling Institutional Revolutionary Party (PRI).
Last November, Mr Salinas was interviewed by Mexican legal officials about another murder, that of his chosen successor as president, Mr Luis Donaldo Colosio.
Mr Carlos Salinas is not charged with any crime, although two million Mexicans recently signed a petition calling for his return to answer corruption allegations, activists claim.
The 16 hour interview with two senior prosecutors of the Mexican attorney general's office took place in the Mexican embassy in Dublin, as did the previous questioning. Mr Salinas told The Irish Times that the main accuser of his brother had been widely reported in the Mexican press as saying that he had been offered a half million dollar bribe to make the accusations.
"That is why it was important to come forward and put this straight," said Mr Salinas.
Mr Raul Salinas has been in jail since early 1995. He is awaiting trial on charges of masterminding the murder, several weeks before the end of the Salinas term, of Mr Jose "Pepe" Ruis Massieu, the general secretary of the PRI.
He is also charged with "inexplicable enrichment" to the tune of up to $200 million while in a state job the then President Salinas had given him.
A source close to the former president has said that Mr Salinas is the victim of an orchestrated campaign by political enemies.
This week a leading opposition politician and a newspaper columnist charged that Mr Salinas was orchestrating his own offensive from Ireland to smear the attorney general's office and weaken the case against Raul.
Shortly after the November questioning in Dublin, President Ernesto Zedillo sacked the then attorney general, Mr Antonio Lozano, and the chief prosecutor in the Ruiz Massieu case.
The case against Mr Salinas's brother has been popularly represented in Mexico as part of a political soap opera - Ruiz had been divorced from the Salinas brothers sister, Adriana - in which the PRI's 67 year rule is to end in the final episode.