The GAA called has said they are "seeking clarity" from Government on the latest coronavirus restrictions.
Given the uncertainty surrounding when the country will be brought down to Level 4 (to allow inter-county) or Level 3 (where club activity is allowed), John Horan said "it remains impossible to plan a revised Master Fixtures calendar for 2021".
After the announcement of the 'Covid 19: Resilience and Recovery 2021' plan, confusion reigned as the document exempted inter-county games along with professional, elite, and horse-racing behind closed doors as a Level 4 sport, with no sports permitted at Level 5.
However, Taoiseach Micheál Martin explained at the following press conference that current list of elite sports exempted under Level 5 restrictions, which doesn’t include inter-county GAA, will be allowed to continue and there may have been a clerical error in the plan.
"We will be seeking clarity on certain aspects of the provisions on sport in the new Government document," John Horan wrote in a letter to club and county secretaries.
"In the interim, and despite any speculation you may read or hear to the contrary, we would again reiterate that the GAA have not decided on what competitions may or may not be facilitated in any revised national fixture programme for 2021.
"Such decisions will be a factor of how much time is ultimately available to us, both for an inter county season and for the broader participation levels that will be necessary for a meaningful club season at both adult and underage levels," he added.
Having to align plans with the Northern Ireland Executive is another complicating factor, the letter adds.
"We also want to assure you that we will publish a revised National Fixtures calendar at the earliest possible opportunity," Horan added.