He said the document could be released later this year or early in 1990.
The documents were released to the public on 25 July 2010.
The documents made available today were released as part of a settlement.
The documents, finally released in 1972, did not support this claim.
She has also started to assess the information in some of the documents released so far.
The Soviet documents are released here for the first time anywhere.
The mayor said last month that he would release similar documents this year.
The document released today shows that Brown was not being honest, he says.
The documents, requested in November 1996, were released last week.
These documents are released to the public between 60 and 100 years after the date of publishing.