The National Council of Provinces (NCOP) on Thursday extended the reporting deadline for the Protection of State Information Bill by a month, to October 31.
The official secrets bill is nearing its final draft, after the African National Congress (ANC) this week made a concession on one of its most contested clauses, and indicated that it would make no more.
The ruling party agreed to scrap clause 1(4), deemed unconstitutional by critics because it sought to make the bill trump all prior information laws, notably the Promotion of Access to Information Act (Paia) of 2000.
Rights advocates had argued that the clause would not only remove the right to access classified records from the purview of Paia, but would criminalise such access without any allowance for public interest in the information.
ANC MP Sam Mozisiwe said the decision to withdraw the clause was prompted by persuasive public input on the bill.
"We as the ANC believe we stand for the people, and we represent the people, and we are of the view that should delete 1 (4) altogether."
The ANC has in recent months agreed to a host of changes to the bill, which is being finalised in an ad hoc committee of the NCOP, after it was passed by the National Assembly late last year amid an outcry.
These include raising the liability threshold for crimes created under the bill to that of intention, by dropping the phrase "ought reasonably to have known".
However, the ANC has insisted on retaining the lower burden of proof with regard to espionage, which carries a 25-year prison sentence.
The party has been accused by the opposition of reneging on a proposal last month to widen the circumstances under which whistle-blowers and journalists may publish classified documents to expose wrongdoing.
It has also stuck to its refusal to include a general public interest defence.
This has been one of main demands of opponents of the bill, but the state security ministry has always ruled it out, saying it would amount to tearing up the legislation.
The committee is expected to have one further meeting with the state security department before referring the bill to the NCOP for debate.
If the changes are approved, it will then be sent back to the National Assembly.
The bill has been years in the making, and has been opposed as an onslaught on freedom on information.
The changes have been welcomed but have not silenced all criticism.
Deputy President Kgalema Motlanthe has indicated that he may ask President Jacob Zuma to refer the bill to the Constitutional Court for certification.