The consultation on the undertakings that will allow News Corporation to buy the 60.1% of BSkyB it does not already own closes at 12pm Friday. A spokeswoman for the DCMS confirmed the deadline would not be extended.
In the past few days the takeover has become increasingly contentious after it emerged that News Corp's Sunday red top News of the World had hacked into the mobile phones of victims such as Milly Dowler.
Avaaz intends to present the final tally of submissions to the Government and host a demonstration outside the Houses of Parliament at 12pm on College Green with figures of a giant Rupert Murdoch as a puppeteer controlling the puppets of David Cameron and culture secretary Jeremy Hunt.
While speculation has suggested that the volume of responses means that a final decision could be delayed until after the summer recess, a spokeswoman for the DCMS could not say when a decision would be announced.
The DCMS has been clear that the issue culture secretary Hunt is able to consider the proposed merger under is media plurality and a spokeswoman from the DCMS said he could not take phone hacking into account.
A DCMS spokeswoman said: "The Secretary of State has always been clear that he will take as long as is needed to reach a decision. There is no 'delay' since there has been no set timetable for a further announcement.
"The consultation closes tomorrow, after which the Secretary of State will consider carefully all the responses submitted and take advice from Ofcom and the Office of Fair Trading before reaching his decision on whether or not to accept the undertakings offered by NewsCorp."
News Corp first made a bid for the proportion of Sky it does not own in June 2010 when it made a proposed offer of 700p a share. Sky's independent directors rejected the offer but said they might accept a higher offer if the deal got regulatory approval.