Mr Fox will leave office after an election in July
In a BBC interview, Vicente Fox also made it clear that once the document is officially published next month, there would be no further investigation.
The Supreme Court had established it was too late to prosecute, he added.
Authorities are alleged to have killed or tortured hundreds of suspected left-wingers in the 1960s and 1970s.
The document awaiting official publication will be the final report by a prosecutor, Ignacio Carrillo, appointed by Mr Fox to investigate what became known as the "dirty war".
"He will have to render his report. It will be placed in an open, public place," the Mexican president told the BBC. "That will be there for history, but legally it's over."
Mr Carillo said earlier that the document would be published in April, and it would not be dissimilar to the leaked version. "It's not going to totally contradict the draft," he told reporters.
His work is concluding ahead of the presidential election in July 2006, after which Mr Fox leaves office.
'Electric shocks'
Earlier this week, a Mexican Magazine and the Washington-based National Security Archive printed material saying Mexicans had a right to know.
The leaked report - which covers 1964 to 1982 and is based partly on declassified Mexican military documents - alleged that the Mexican government and military committed "crimes against humanity".
Hundreds of activists disappeared during the "dirty war"
It said units detained or summarily executed men and boys in villages suspected of links to rebel leader Lucio Cabanas. Detainees were forced to drink gasoline and tortured with beatings and electric shocks.
Bodies of dozens of leftists were dumped in the Pacific Ocean during helicopter "death flights" from military bases in Acapulco and elsewhere, the leaked report added.
Mr Fox set up an office in 2002 to probe possible human rights violations under the administrations of presidents Gustavo Diaz Ordaz (1964-70), Luis Echeverria (1970-76) and Jose Lopez Portillo (1976-82).
The office presented the report to the special prosecutor investigating past abuses on 15 December, but it was not released.
Correspondents say Mr Carrillo's work was thwarted by legal obstacles and a lack of resources, and he himself has recently described it as deficient.
The fatal blow came when the Mexican Supreme Court rejected Mr Carrillo's attempt to bring to trial former senior officials, including ex-president Echeverria, saying that legally it was too late for prosecutions.
A leaked draft of a report on instances of state repression during Mexico's "dirty war" has been called into question by top officials. The document will be officially published next month.  Report author, Ignacio Carrillo, assigned to the task by President Fox, commented by saying, "He will have to render his report. It will be placed in an open, public place," and "that will be there for history, but legally it's over."  This being a reference to the fact that the Supreme Court has ruled that it is too late to prosecute possible offenders.

Carrillo claims, however, that his report is similar to the recently leaked draft.  He said, "It's not going to totally contradict the draft."  The draft was published by a Mexican magazine, claiming that the public has a right to know.  The basis for the report is recently declassified military documents from the years 1964 – 1982.  Carrillo also claims that his work was hindered by resistance from the courts, bad resources, and people involved being unwilling to cooperate.

The Dirty War refers to the use of state terrorism in Latin America in a period from the 1960s to the 1980s, usually targeted at groups opposed to the government (usually leftist groups).  Much controversy exists in the region about what is to be done with alleged offenders in the Dirty War.