The 27-page paper was published yesterday and interested parties have until 5 January to respond. This allows just 17 working days, because of bank holidays over the Christmas and New Year period.
The Compact, which outlines how the public and voluntary sectors should behave towards each other, says that government should hold, wherever possible, a 12-week consultation that engages meaningfully with relevant stakeholders.
The paper describes the consultation period as "regrettably short" and acknowledges it falls out "outside the Compact".
It says deviation from the Compact "will be mitigated by more targeted engagement", but does not give any details of this.
In a statement, Compact Voice, which represents the voluntary sector on the Compact, said: "Compact Voice is concerned that with the pace of government change, shorter time frames are becoming commonplace, with insufficient effort being put into meaningful consultation that follows Compact principles.
"We will be seeking urgent clarification from OCS about how it intends to engage, to ensure that the views of stakeholders are taken into account during this consultation, especially given the very short time frames.
"When considering a topic as important as the role of the voluntary and community sector in delivering public services, it is vital that consultation is both meaningful and as exhaustive as possible."
An OCS spokesman said the time frame was due to the "short window of opportunity between the spending review and the beginning of the 2011-2014 spending period".
He added that the green paper would feed a public service reform white paper that was due to be published early in 2011.