Football Association chairman Greg Clarke has said it is hard to see fans returning to matches “any time soon”.
If the Premier League and Football League seasons resume, those matches will be played behind closed doors.
The Premier League is also preparing for the possibility of playing the 2020-21 season without fans.
“The reality is that we just don’t know how things are going to pan out,” Clarke wrote in a letter to the FA governing council.
“But with social distancing in place for some time to come we do face substantial changes to the whole football ecosystem.
“For example it’s hard to foresee crowds of fans – who are the lifeblood of the game – returning to matches any time soon.”
Clarke warned of an FA budget cut of £75m this year, with a “worst-case scenario” of a £300m deficit over the next four years impacting “every area of the game”.
Is there a split between Premier League clubs?
Top-flight clubs have been told that using up to 10 neutral stadiums will be the only way to complete the season.
Brighton say they are “not in favour” of using neutral venues because it may affect the “integrity” of the league.
Clubs near the bottom of the table feel it is unfair to play in such different conditions when at risk of relegation.
A growing number of Premier League clubs are open to playing the remaining fixtures at neutral venues but with the threat of relegation removed.
A larger 23-team division has been suggested, with three teams added from the Championship. But with an already crowded calendar, that is not an option currently being considered by the Premier League.
The BBC has learned the Premier League fears six or seven clubs are opposed to neutral stadiums.
But there is also a sense that within that group there are disagreements over how they want the season to end.
The neutral stadium proposal needs 14 out of 20 clubs to vote in favour for it to be adopted.
Prime Minister Boris Johnson will reveal his “roadmap” out of lockdown on Sunday and that means that the Premier League’s next meeting will be delayed until next week.
What are we up to with ‘Project Restart’?
The Premier League has been suspended since 13 March because of the coronavirus pandemic but all clubs are committed to playing the 92 remaining fixtures of the 2019-20 season if and when safe to do so.
Plans to resume the league have been labelled ‘Project Restart’. The league is hopeful of a potential 8 June restart and finishing at the end of July to fit in with Uefa’s European competition plans. This would require full training to begin by 18 May.
In addition to the neutral venues, the league would also need up to 40,000 tests for players and staff if plans to play the outstanding games behind closed doors are pursued.
On Friday, after their most recent meeting by video conference, Premier League clubs reiterated a commitment to resuming the season “when safe and appropriate to do so”.
What about players returning to training?
A number of clubs reopened their training grounds for individual training last week.
If full training is resumed before social distancing rules are relaxed, BBC Sport understands players will be tested for coronavirus twice a week and would be screened for symptoms every day.
In addition, players must arrive at training grounds in kit and wear masks at all times.
What has been the reaction from players?
Manchester City striker Sergio Aguero has said players are “scared” about the prospect of returning to action. Team-mate Kevin de Bruyne added: “I don’t think people are really afraid for themselves, but for their family. That is mainly the problem for many people.”
Brighton striker Glenn Murray, meanwhile, says some proposed protocols around the Premier League’s return to action, such as wearing face masks, are “farcical”.
What have clubs said?
Only a few clubs have spoken publicly.
In addition to Brighton’s chief executive Paul Barber, Southampton chief executive Martin Semmens told BBC Radio Solent that it would not be appropriate for the Premier League to plan for an immediate return.
Crystal Palace chairman Steve Parish has said the protocols in place would “render Premier League football one of the safest places in society to co-exist”.
Writing in the Sunday Times, he added that the issues facing football could be in place for months and affect next season so “the more we can work out now, the better chance we have of coming out of this with the game we all love in position to recover over time”.